Author: Adam Simmons
Date published: April 19th 2023
Table of Contents
Introduction
LCDs panels have dominated the monitor market for many years and whilst they continue to do so, a few OLED alternatives are also slipping in. The ASUS PG27AQDM of the ROG Swift OLED series is one such offering, designed for a fluid QHD gaming experience in both SDR and HDR. The usual OLED benefits are touted such as exceptional contrast, strong viewing angles and pixel responsiveness – combined with quite a generous colour gamut and some good peaks of HDR brightness. We put this screen to the test in a range of tasks, including general desktop usage, movie watching and of course gaming.
Specifications
The monitor adopts a 26.5” WOLED panel from LG Display, with 2560 x 1440 resolution and 240Hz refresh rate. 10-bit colour is supported, whilst a 0.03ms grey to grey response time is specified – as usual don’t pay much attention to such figures, though OLED technology is known to be very strong in this respect. The key ‘talking points’ for this monitor have been highlighted in blue below, for your reading convenience (there are many, as you can see).
The monitor has a distinctly ‘ROG’ appearance, with a solid and sharp-lined ‘tripod style’ stand base – coated metal, finished in dark grey. Some ‘Aura RGB’ (though technically red, not RGB) lighting elements are visible at the front, including red shapes (one at front, one at each side) on the base and a red down-firing projector beneath it. A logo on the protruding central area of the bottom bezel indicates the power status of the monitor and can be made to glow red when the screen is on if you wish. These lighting features are explored in the OSD (On Screen Display) video. The central protrusion of the bottom bezel, with glossy black front face, also houses some of the monitor electronics. This allows the screen to be slimmer elsewhere. The bezels are dual-stage at all sides, with slim panel border flush with the rest of the screen and hard outer part. The bezels are particularly slim at the top and sides – ~7mm (0.28 inches). The bottom bezel is thicker, ~9mm (0.35 inches) or ~26mm (1.02 inches) if you include the central protrusion. The screen also has a slim ‘active area’ between the panel border and the image which the entire image periodically moves around in if the ‘Screen Move’ feature (explored shortly) is active – a few mm thick or so. As usual, it’s the screen itself which is the main feature of interest from the front and it has a medium or ‘relatively light’ matte anti-glare screen surface, explored shortly. The OSD is controlled by a joystick with two accompanying buttons – one of which is a dedicated power button. The video below runs through the menu system including the ‘Aura RGB’ feature and accompanying ‘DisplayWidget Center’ software. It also explores the changes we made for our ‘Test Settings’, covered later in the review. OLED technology is often associated with a potential image retention or ‘burn-in’ risk. This can include temporary afterimages which are shown on the screen (image retention), or in more severe cases and over a longer period it can include permanent damage (‘burn-in’). One of the features ASUS is keen to promote with this model is the “highly efficient custom heatsink”, which increases heat dissipation and can help reduce the risk of burn-in. The monitor includes a few integrated features designed to offer some degree of protection from image retention or burn-in, which are located in the OSD under ‘System Setup’ – ‘Screen Protection’. ‘Pixel Cleaning’ is a maintenance cycle that the monitor is supposed to run after each cumulative 8 hours of use. It can also be run manually if required. If this cycle is due to be run the monitor should do this automatically when the monitor goes into standby (or if you turn it off with the power button) to avoid disruption. The cycle lasts around 6 minutes but can be interrupted if required by waking up or powering on the monitor. The power indicator flashes orange when pixel cleaning is in progress. If you have ‘Pixel Cleaning Cycle Reminder’ enabled it will display a message towards the bottom right of the screen for ~15 seconds after the selected interval (2, 4 or 8 hours). This is just a message to remind you to manually run the cycle after this interval. Whilst the automatic scheduling of the cycle to run every 8 hours in a non-disruptive way is how this is supposed to work, based on what ASUS has told us, we’re not sure it was actually doing this on our unit. We’d recommend running the cycle manually when it’s convenient (e.g. before bed or when making a meal) perhaps a few times a day, depending on how much you’re using the monitor. ‘Screen Move’ occasionally nudges the entire image over. There are 4 settings; ‘Strong’, ‘Middle’ and ‘Light’ and ‘OFF’. These affect how significant the shift will be, with the shift seeming to occur pretty much continuously regardless of setting used. There’s a small active area (shown in image below, camera flash used to help highlight it) that’s not visible in most light when using the monitor to help accommodate this. On our unit we observed shifting beyond the active area so you’ll lose part of the image – even with the ‘Light’ setting where the shift is lowest. With the seemingly continuous movement and cropping of the image we found this far more obtrusive and annoying, even if potentially more effective, than what was implemented on the AW3423DW – which is just as well given the feature can’t be disabled on the Alienware. ‘Adjust Logo Brightness’ is designed to selectively reduce the brightness of bright static content which is displayed on the screen for extended periods of time. Game HUD elements or buttons in a program with bright text or designs that don’t move for prolonged periods could trigger this behaviour. This feature is disabled by default. Our general recommendation would be to ensure the ‘Pixel Cleaning’ maintenance cycle is run periodically, when it’s convenient and you don’t need to use the monitor for several minutes. You should also keep ‘Screen Saver’ active, unless you find it’s dimming the screen when you don’t want it to for some reason. We’d also recommend setting Windows to ‘Turn off the display’ after a short period of time. Unlike the monitor’s ‘Screen Saver’ feature, this won’t help if you’re running a full screen application – for example if you pause a game and the screen is almost entirely static. We found ‘Screen Move’ annoyingly obtrusive and disabled ‘Adjust Logo Brightness’ for consistency in the review as that could potentially affect observations or readings if it activated. So, we ran the ‘Pixel Cleaning’ cycle periodically and used ‘Screen Saver’ but disabled ‘Screen Move’ and ‘Adjust Logo Brightness’. We set Windows to ‘Turn off the display’ after 20 minutes of inactivity but didn’t take any additional precautions during the review such as auto-hiding the taskbar or turning the monitor off as soon as we left the room. We’d suggest considering a shorter period than 20 minutes before the display is set to turn off, but this was a practical time to use for reviewing purposes. You may wish to set the taskbar to auto-hide as an additional precaution, as this is content which will remain largely static when on the desktop. If leaving the taskbar active we’d recommend selecting a dark theme (e.g. in ‘Personalisation’ – ‘Colours’ select ‘Dark’ for ‘Choose your default Windows mode’). We didn’t experience any ‘burn-in’ or even mild image retention when using the monitor over the review period. Though this was limited to several days and clearly doesn’t represent long-term use of the monitor. This monitor uses a medium or ‘relatively light’ (so slightly lighter than some we’d classify as ‘medium’) matte anti-glare screen surface. The screen surface texture isn’t as smooth as some matte surfaces, imparting a bit of a grainy look to brighter content. There’s also some layering in front of the image, which is to say you might become somewhat more aware of the structure of the screen surface in front of the image compared to significantly lighter matte screen surfaces. It shows these characteristics more strongly than most ‘competing’ IPS models, which use light or very light matte screen surfaces. The monitor offers relatively strong glare-handling, diffusing ambient light quite heavily across the screen surface. You don’t need to worry about reflections as you will see with glossy screen surfaces in some environments. And even with fairly strong light striking the screen directly you don’t get the same sharper glare patches you may see on light to very light matte screen surfaces. The diffused ambient light creates a hazing of the image, however. The screen surface doesn’t exhibit the colourful lightening up we observed on the QD-OLED AW3423DW (first photo) from a normal viewing position, though this is observed with a gold to purple tint from a sharp angle and with strong light striking the screen surface (second photo).
*10-bit can be selected in the graphics driver at any refresh rate, up to the native resolution using DP 1.4 (with DSC). 10-bit and 12-bit can be selected at up to 60Hz when using HDMI. The panel itself is 10-bit, so selecting 12-bit involves an additional 2-bit dithering stage applied by the monitor’s scaler to facilitate viewing 12-bit content. The bit depths listed here are using a Full Range RGB signal.
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Features and aesthetics
The screen is very slim at thinnest point (~4mm or 0.16 inches), bulking out more centrally to ~50mm (1.97 inches). The stand is fully adjustable, including; tilt (5° forwards, 20° backwards), swivel (30° left, 30° right), height adjustment (110mm or 4.33 inches) and pivot 90° either direction into portrait. The swivel adjustment was a bit stiff and the height adjustment took a fair bit of pressure to get going, but movement was smooth once it did. Our unit was brand new and this may loosen up over time. At lowest stand height the bottom edge of the screen, including central protrusion, sits ~70mm (2.76 inches) above the desk surface, with the top of the screen ~438mm (17.24 inches) above the desk. The total depth of the monitor including stand is ~274mm (10.79 inches), with the screen sitting ~40mm (1.57 inches) back from the frontmost point of the stand. So the screen takes up a decent chunk of desk depth, though not an extreme amount as far as ROG models or some other gaming monitors go. Another lighting element, controlled alongside all other lighting on the base, is illuminated ‘SWIFT’ lettering running vertically down the centre of the stand neck.
The rear of the monitor is mostly dark matte plastic, with a central area including a ‘mesh’ texture towards the top and right. A further ‘Aura RGB’ element is included here, an ROG logo. The stand has a dark matte plastic neck and attaches centrally with a quick-release catch (push downwards to release) beneath the attachment point. 100 x 100mm VESA mounting is supported using an included adaptor bracket. The ports face downwards and include; a DC power input (external ‘power brick’), a 3.5mm headphone jack, 2 HDMI 2.0 ports, DP 1.4 (with DSC) and 2 USB 3.2 Gen 1 ports plus Type-B upstream. Other features of note include; a K-Slot in the port area, a tripod or camera screw mount at the top of the stand and a split region in the middle of the stand which can be used as a cable tidy. There are no integrated speakers on this model. A power cable and adaptor, HDMI 2.0 cable, DP cable and USB 3.2 cable is included as standard, but this can vary by region.
2560 x 1440 @240Hz plus HDR and Adaptive-Sync can be leveraged via DP 1.4 (with DSC), with HDMI 2.0 providing those features but limited to 2560 x 1440 @120Hz. AMD FreeSync Premium and Nvidia ‘G-SYNC Compatible’ is supported via DP and HDMI on compatible systems. Although the bandwidth of the HDMI ports is limited (equivalent to HDMI 2.0), ‘HDMI 2.1 VRR’ is supported when the monitor is connected to HDMI 2.1 ports. This allows systems that don’t support Adaptive-Sync (such as the PS5) to use VRR technology and also enables ‘G-SYNC Compatible’ via HDMI on suitable GPUs. Compatible Intel graphics hardware can also leverage Adaptive-Sync. The images below show the refresh rates supported for the native 2560 x 1440 (WQHD or 1440p) resolution via DP (top image) and HDMI (bottom image).
The images below show the refresh rates supported for 1920 x 1080 (Full HD or 1080p), with the same options listed via both HDMI and DP. The first image shows the resolutions categorised in the EDID of the monitor as ‘TV’ resolutions and listed here under ‘Ultra HD, HD, SD’. The second image shows resolutions categorised in the EDID and listed here as ‘PC’ resolutions.
A ‘4k x 2k, 3840 x 2160’ downsampling mode is included via HDMI at up to 60Hz, shown in the image below. This is particularly useful for the Xbox Series X which doesn’t allow HDR to be used at lower resolutions than this.
If you’re intending to use the monitor with the PS5 or Xbox Series X/S, be aware that a small settings tweak may be required to ensure 120Hz is selectable for supported resolutions. Details can be found in this article.
Image Retention and burn-in
‘Screen Saver’ will dim the screen if static content is detected. This is far less aggressive than the sort of ASBL (Automatic Static Brightness Limiter) feature commonly found on OLED TVs such as the LG C2 series and less likely to activate. If the signal (contents on the screen) changes very little for several minutes, the screen will dim – unless it’s already set to a very low brightness. Slight changes such as the system clock changing or a small blinking cursor on the screen won’t prevent the feature from activating – we found this feature effective at dimming the screen when not in use and not annoying us by activating when we didn’t want it to.
Calibration
Subpixel layout and screen surface
The first image below is a macro photograph taken on Notepad with ClearType disabled. The letters ‘PCM’ are typed out to help highlight any potential text rendering issues related to unusual subpixel structure, whilst the white space more clearly shows the actual subpixel layout alongside a rough indication of screen surface. The second image shows a vertical stripe with single pixel ‘dots’ of red, white, blue and green to better show the ordering of the subpixels. The monitor uses an RWBG subpixel layout (sometimes inaccurately referred to as WRGB or other variants such as RWGB with incorrect ordering), with an ‘unfiltered’ (white) subpixel in addition to the usual R, G and B. Most Windows users will be used to the representation of text using ClearType, which is enabled by default and has been for many years. You can optimise this for RGB or BGR, but not specifically RWBG, with additional tweaks according to taste. For the first sample set on ‘ClearType Text Tuner’ (1 of 5) we’d recommend selecting the first option which will optimise for RGB rather than BGR – the latter appeared to give an even more fringed appearance to text with a more noticeable displacement to the fringe. For the remaining options it really comes down to personal preferences. Our fringing article specifically looks at the issues related to this RWBG subpixel layout, including some linked to ClearType and some that extend beyond text and have nothing to do with subpixel rendering.
WOLED subpixels individually lit
Testing the presets
The PG27AQDM features a range of ‘GameVisual’ preset modes; ‘Scenery’, ‘Racing’, ‘Cinema’, ‘RTS/RPG’, ‘FPS’, ‘sRGB’, ‘MOBA’ and ‘User’. These presets alter the default values for various settings in the OSD, whilst some lock off various settings and may make changes to things such as gamma behaviour and colour balance which can’t be counteracted by manual adjustment in that preset. Some settings including those found in the ‘Image’ section of the menu apply universally and aren’t specific to each preset. You can save and recall 2 sets of settings in ‘MyFavorite’ – ‘Customized Setting’. We run through these presets in the OSD video but will instead focus on manual adjustment of various other settings for this section. The table below provides key readings (gamma and white point) taken using a Datacolor SpyderX Elite alongside general observations.
Our test system uses Windows 11 with an Nvidia RTX 3090 connected via DisplayPort. Additional testing was performed via HDMI and also using an AMD Radeon RX 580, but observations on this table didn’t differ significantly between inputs or GPUs. The monitor was left to run for over 2 hours before readings were taken and observations made, without any additional monitor drivers or ICC profiles specifically loaded. Aside from our ‘Test Settings’, where various adjustments were made, assume factory defaults under ‘Racing Mode’ were used with ‘Uniform Brightness’ (explored later) enabled. The monitor was set to 240Hz in Windows, although this didn’t significantly affect the values or observations in this table. When viewing the figures in this table, note that for most PC users ‘6500K’ for white point and ‘2.2’ for gamma are good targets to aim for. Individual targets depend on individual uses, tastes and the lighting environment, however.
Preset Mode Gamma (central average) White point (kelvins) Notes Gamma = 2.2 (Factory defaults) 2.2 7043K A vibrant look with a bit of a cool tint. Excellent consistency, gamma averages ‘2.2’ but deviates in places as explored shortly. Gamma = 1.8 1.9 7052K As above but quite a washed out look due to low gamma. Gamma = 2.0 2.1 7019K As above, slight increase in depth. Gamma = 2.4 2.3 7034K As default with extra depth due to higher gamma. Gamma = 2.6 2.5 7064K As above, even more depth and a very ‘contrasty’ look – heavy crushing of dark detail. Display Color Space = sRGB 2.2 6997K An sRGB emulation setting which clamps the gamut closer to sRGB. Saturation and vibrancy reduced with more faithful output of standard sRGB content. Cool tint by default, but excellent flexibility (settings aren’t locked off), some shades a touch undersaturated due to gamma being below desired ‘2.2’ in places. Blue Light Filter = Level 1 2.2 8370K Greater blue light output than factory defaults, with a clear cool tint. Blue Light Filter = Level 2 2.2 7788K As above, still higher white point with greater blue light output than factory defaults. Blue Light Filter = Level 3 2.2 7231K Quite similar blue light output and white point to factory defaults, with green tint added. Blue Light Filter = Level 4 2.2 5655K A fairly effective LBL setting, significantly reducing blue channel and greatly cutting down blue light output. Further blue light reduction achieved by reducing brightness. The green channel is very strong, giving an obvious green tint. Color Temp. = 4000K 2.2 4343K A highly effective LBL setting, with significantly reduced blue channel (and hence reduction in blue light). The green channel is weakened somewhat as well, so there isn’t a green tint but instead a warm amber tint we found our eyes adapted to better. Color Temp. = User (100 per channel) 2.2 9299K As factory defaults with very cool tint (icy appearance – like a weird filter is applied). Test Settings (see below) 2.2 6523K As factory defaults with corrected white point and colour channels. Vibrant and well-balanced overall.
Straight from the box the monitor is set to its ‘Racing Mode’ preset, using the full native gamut (‘Display Color Space = DCI-P3’). The image appeared vibrant with a bit of a cool tint. Gamma averaged ‘2.2’ and tracked the curve reasonably well overall. The gamma was a bit too high for dark shades which meant some dark detail was slightly more masked than it should be. Gamma was also bit too low for bright shades, meaning some bright detail was a touch more blended than it should be. There were also some changes in gamma for brighter shades depending on brightness. The changes were less pronounced than we saw on the AW3423DW and gamma always averaged ‘2.2’, but we wouldn’t typically see measurable gamma changes in the curve for LCDs as brightness is changed. The graphs below show gamma with ‘0’, ‘50’ and ‘100’ brightness, respectively, followed by the results under our ‘Test Settings’. Gamma tracking there is quite comparable to the factory defaults. Note that results were similar with ‘Display Color Space’ set to ‘sRGB’ rather than ‘DCI-P3’. These graphs just give a general idea of gamma behaviour but lack the precision or resolution to clearly show the low-end gamma uplifts we described. Given the intended uses for the monitor, inter-unit variation and generally pleasing performance of our unit with OSD tweaking alone we won’t be using any ICC profiles in this review or including any measurements or graphs using them. We wouldn’t recommend using them unless created for your specific unit using your own calibration device. But we appreciate some users still like to use profiles and some aspects such as gamut mapping for colour-aware applications can be useful. You can download our ICC profile for this model, which was created using our ‘Test Settings’ as a base. You can also download our sRGB profile which was created using and designed for the ‘Display Color Space = sRGB’ setting, with the factory defaults of the screen used (‘Uniform Brightness’ enabled). Amongst other things, this re-tuned the gamma for tighter adherence to the ‘2.2’ curve on our unit – but be aware of inter-unit variation. And note again that these ICC profiles are not used in the review. We prefer to analyse things in a more visual and qualitative way, but using the ‘sRGB Mode’ out of the box without a profile active (‘Uniform Brightness’ enabled) we can confirm an average DeltaE of 1.15 within the sRGB colour space recorded with our SpyderX Elite, using the same 24 test patches analysed visually deeper into the review (SpyderCHECKR 24). Note that shade 1F (cerulean) is often recorded with a high error in this test, though it’s still a touch high here. ASUS only claims an average DeltaE <2 in their marketing material and that is achieved here - each unit includes an individual factory calibration report with further measurements, but this was missing on our test sample. This monitor includes TÜV Low Blue Light (Hardware Solution) certification, with its peak of blue light shifted to less energetic wavelengths (456nm reliably recorded by multiple sources for the panel used compared to the more ‘standard’ ~450nm). This provides potential viewing comfort benefits, but there are many factors to consider when it comes to viewing comfort and everybody’s eyes are different. In addition to this, the monitor includes ‘Blue Light Filter’ Low Blue Light (LBL) settings which are designed to reduce blue light output of all wavelengths and create a warmer look. Reducing exposure to blue light can aid viewing comfort, whilst the warmer look to the image can be useful for relaxing viewing. Something that could be particularly beneficial in the hours leading up to sleep. In practice this setting actually increased blue light output compared to default, unless set to ‘Level 4’ (strongest effect). The green channel remained strong and there was a clear green tint to the image, however. We prefer setting ‘Color Temp.’ to ‘4000K’ which is a highly effective LBL setting without the green tint and a warm amber look we found our eyes adjusted to more readily over time. We used this for our own viewing comfort in the evenings, but not for specific testing beyond that involving this particular setting. For our ‘Test Settings’ we stuck to the factory default ‘Racing Mode’ preset and made a few adjustments, including to brightness and colour channels. We enabled ‘Uniform Brightness’, too. Note that individual units and preferences vary, so these settings are simply a suggestion and won’t be optimal for all users or units. We’ve included the refresh rate used in Windows, just for reference. These settings only apply to SDR, HDR has separate settings associated with it (is far more restrictive) and is explored in the relevant section of the review. We used the defaults under ‘HDR Gaming’ for HDR. Adaptive-Sync = On GameVisual = Racing Mode Brightness = 64 (according to preferences and lighting) Uniform Brightness = On Color Temp. = User R = 100 G = 93 B = 80 Refresh rate (Windows setting) = 240Hz Note that the firmware can be upgraded via ASUS’s support page for the monitor. The latest firmware available at time of review was loaded onto our unit before we received it (reported as MCM103). An X-Rite i1Display Pro Plus (Calibrite ColorChecker Display Plus) was used to measure the luminance of white using various settings, including those covered in the calibration section. Because of the self-emissive nature of this display, black depth is ‘0’ and contrast ratio essentially infinite as measured with the colorimeter regardless of settings used. Blue highlights indicate the results under our ‘Test Settings’ and with HDR active. ‘HDR Game’, ‘HDR Movie’ and ‘HDR Console’ all performed identically in our testing. Black highlights indicate the highest white luminance recorded under SDR. Assume any setting not mentioned was left at default, with the exceptions noted here or in the calibration section. There’s a setting called ‘Uniform Brightness’ which will limit the brightness but also prevent aggressive ABL (Automatic Brightness Limiter) behaviour, explored below. Unless stated otherwise, the ‘Uniform Brightness’ function was in use for the purposes of this table under SDR as this is a setting most will want to enable. A few readings are also given at various OSD brightness settings with the function disabled. Note: The test patch used under SDR is a fairly large white box (60mm x 60mm) in the centre of the screen, surrounded by a bit of light grey with black text for the UI elements of the program. The desktop background is shown surrounding that complete with desktop icons to the left and the taskbar at the bottom (example from another screen). If you want the highest potential brightness under SDR, you’ll have to put up with the aggressive ABL (Automatic Brightness Limiter) behaviour of ‘Uniform Brightness’ disabled. The entire screen will dim significantly if a relatively large amount of bright content is displayed. We recorded fluctuating brightness levels depending on the desktop background displayed – a range of wallpapers were observed, as were solid shades including black and white. The brightness range recorded for each setting is provided. The recorded fluctuations with ‘Uniform Brightness’ are very small even at higher brightness levels. We didn’t find the fluctuating brightness obvious by eye – unlike the much more aggressive ABL some OLED screens use and which this screen uses with ‘Uniform Brightness’ disabled, which can be annoying for desktop usage.
Gamma '0' brightness
Gamma '50' brightness
Gamma '100' brightness
Gamma 'Test Settings'
Test Settings
Contrast and brightness
Contrast ratios
Monitor Settings White luminance (cd/m²) Black luminance (cd/m²) Contrast ratio (x:1) 100% brightness 257 - 260 0.00 ∞:1 80% brightness 211 - 213 0.00 ∞:1 60% brightness (Factory Default if using Uniform Brightness) 166 - 168 0.00 ∞:1 40% brightness 118 - 119 0.00 ∞:1 20% brightness 71 0.00 ∞:1 0% brightness 21 0.00 ∞:1 100% brightness (Uniform Brightness disabled) 216 - 475 0.00 ∞:1 50% brightness (Uniform Brightness disabled) 160 - 194 0.00 ∞:1 0% brightness (Uniform Brightness disabled) 21 - 22 0.00 ∞:1 HDR 6500K / HDR 8200K (1% white, peak)* 926 / 1092 0.00 ∞:1 HDR 6500K / HDR 8200K (4% white, peak)* 925 / 1086 0.00 ∞:1 HDR 6500K / HDR 8200K (9% white, peak)* 925 / 1085 0.00 ∞:1 HDR 6500K / HDR 8200K (25% white, peak)* 462 / 530 0.00 ∞:1 HDR 6500K / HDR 8200K (49% white, peak)* 252 / 289 0.00 ∞:1 HDR 6500K / HDR 8200K (100% white, sustained)** 154 / 167 N/A N/A Gamma = 1.8 164 - 166 0.00 ∞:1 Gamma = 2.0 164 - 165 0.00 ∞:1 Gamma = 2.4 166 - 168 0.00 ∞:1 Gamma = 2.6 166 - 168 0.00 ∞:1 Display Color Space = sRGB 165 - 167 0.00 ∞:1 Blue Light Filter = Level 1 172 - 175 0.00 ∞:1 Blue Light Filter = Level 2 171 - 173 0.00 ∞:1 Blue Light Filter = Level 3 170 - 172 0.00 ∞:1 Blue Light Filter = Level 4 168 - 170 0.00 ∞:1 Color Temp. = 4000K 129 - 132 0.00 ∞:1 Color Temp. = User (100 per channel, 100% brightness) 257 - 274 0.00 ∞:1 Test Settings 165 - 167 0.00 ∞:1 Test Settings (100% brightness) 243 - 245 0.00 ∞:1
*HDR measurements were made using this YouTube HDR brightness test video, running full screen at ‘1440p HDR’ on Microsoft Edge. We had some issues running this particular test on Google Chrome on this monitor, where brightness was significantly lower than anticipated – and lower than observed for normal HDR content on Chrome. The maximum reading using the patch size (measurement area) specified in the table was used. The black luminance was taken at the same point of the video with the colorimeter offset to the side of the white test patch, equidistant between the test patch and edge of the monitor bezel.
**These readings were taken using the above test. A reading was taken using a white screen fill (‘all pixels’), 30 seconds after it was displayed. This is used to represent the sustained luminance level the monitor can provide under HDR, rather than the peak luminance achieved for smaller sections of the screen. Because the entire screen is white for this test, black luminance levels can’t be read and an HDR contrast reading can’t be ascertained.
The monitor provided a peak luminance of 257 – 260 cd/m² under SDR with ‘Uniform Brightness’ enabled and 216 – 475 cd/m² with it disabled. In practice the stability with ‘Uniform Brightness’ enabled was much preferred. Whilst this ~260 cd/m² isn’t as bright as some some LCDs will provide, it’s high enough for most users and use cases as people generally set their monitors some way between 100 – 200 cd/m². There are of course exceptions to this. It’s also in-line with the reading we took on the QD-OLED AW3423DW, which is generally regarded as a decent OLED performer in that respect. The strong overall uniformity and contrast can also make the screen appear somewhat brighter than with an equivalent setting on an LCD. For reference, we recorded 243 – 245 cd/m² with our ‘Test Settings’ at ‘100’ brightness which indicates how bright the monitor can get with colour channels corrected (including ~6500K colour temperature). The minimum luminance recorded was 21 cd/m², which is rather dim and should be fine for even quite light-sensitive users who tend to prefer dim settings.
Under HDR the peak luminance recorded was 926 cd/m² with the ‘6500K’ setting and 1092 cd/m² with the ‘8200K’ setting, with a moderate drop off by 25% patch size and a further significant drop beyond that, down to 154 cd/m² (‘6500K’) or 167 cd/m² (‘8200K’). We recorded a white point ~6700K under HDR using the ‘6500K’ setting and ~8800K using the ‘8200K’ setting, though the exact white point varies depending on brightness. The ‘8200K’ setting gave a clear cool and icy tint to the image, can accelerate eye fatigue and we don’t feel the recorded increase in brightness is sufficient to warrant using that setting over ‘6500K’. The HDR luminance data for the two brightness settings is shown in the graph below, for those preferring a graphical representation. When taking HDR brightness readings peak levels were sometimes reached only very briefly, with some fluctuation at various values slightly below that level (<80 nits variation, but worth noting). We record true peak readings here which mean the highest value observed for a given patch size, except for the sustained reading at a 100% patch size. The QD-OLED Dell Alienware AW3423DW is also included in the graph, for comparison.
In this graph, you can see that the AW3423DW provides a superior peak at 1% patch size compared to the PG27AQDM using its comparable neutral white point setting (‘6500K’). At a 4% patch it’s similar, whilst at 9% and 25% it drops below, only to rise a bit above again for 49% and 100% patch sizes. This ‘trend’ is the same regardless of the white point setting used on the ASUS. We draw subjective comparisons a little later to explain how this can manifest in normal HDR content, but overall the ASUS pushes the brightness of the panel it uses well.
PWM (Pulse Width Modulation)
The PG27AQDM does not use PWM (Pulse Width Modulation) to regulate the brightness of its pixels at any level. Instead, DC (Direct Current) is used to moderate brightness. As is common for OLED screens, the screen uses low amplitude oscillation – so there’s a slight cyclical dip in brightness in sync with the refresh rate, for example every 4.17ms at 240Hz. This was recordable via oscilloscope and can be observed by a camera with certain settings, but is very different to the more pronounced brightness changes accompanying PWM. As such, it shouldn’t be bothersome to most users and the monitor can be considered ‘flicker-free’ as advertised. Sensitive users could potentially find this bothersome, particularly at lower refresh rates. We’ve communicated with some individuals who are particularly sensitive to PWM flickering but find OLED screens with similar brightness regulation comfortable to view, so sensitivity to PWM doesn’t necessarily mean this will be problematic.
Luminance uniformity
This monitor uses OLED technology with self-emissive pixels rather than relying on a backlight. As such, there is no backlight bleed or associated clouding. Whilst observing a black background in a dark room, using our ‘Test Settings’, we saw a pure blackness – as if the screen was switched off. This is shown in the image below, which is simply for reference and included as we usually do so at this point in the review. Any patchiness in the image is due to the camera or image processing, not the monitor. The luminance uniformity was very good. The maximum luminance was recorded at ‘quadrant 6’ to the right of centre (152.4 cd/m²). The greatest deviation from this occurred at ‘quadrant 7’ to the left of centre (142.0 cd/m², which is 7% dimmer). The average deviation between each quadrant and the brightest recorded point was 3.38%, which is strong. Remember that individual units vary when it comes to uniformity and you can expect further deviation beyond the points measured. But with its lack of backlight and direct emission from the pixels, relatively strong uniformity can be expected in this area. The contour map below shows these deviations graphically, with darker greys representing lower luminance (greater deviation from brightest point) than lighter greys. The percentage deviation between each quadrant and the brightest point recorded is also given. The SpyderX Elite was also used to analyse variation in the colour temperature (white point) for the same 9 quadrants. The deviation between each quadrant and the quadrant closest to the 6500K (D65) daylight white point target was analysed and a DeltaE value assigned. Darker shades are also used on this map to represent greater deviation from 6500K. A DeltaE >3 represents significant deviation that may be readily noticed by eye. Results here were excellent, with no significant deviations recorded – the bottom central region was recorded as closest to 6500K, with a maximum DeltaE of 1.7 recorded to the right of centre. Note again that individual units vary when it comes to uniformity and that you can expect deviation beyond the measured points. Our unit appeared somewhat cooler at the very far right, for example. Also note that this colour temperature measurement doesn’t account for the green channel strength, which can also vary at different points of the screen. This wasn’t a significant issue on our unit, with only minor variation observed. In addition to the quantitative testing above, we performed a subjective assessment of the uniformity of a variety of dark and medium shades, including 5% grey and 50% grey. Some OLED screens are susceptible to uniformity issues such as splotches or obvious striations when viewing large areas of flat shades such as this, giving an inconsistent appearance that some users refer to as ‘DSE’ (‘Dirty Screen Effect’). In this case we observed minor striations on some shades, mainly vertical but some horizontal as well. Dark grey shades (such as #282828) showed this most clearly, but this was still not extreme as far as such issues go. We’ve included a photo of the screen displaying this shade below to give an idea of the level of ‘DSE’ and also a shift in tone to the grey – though this tone shift is somewhat exaggerated in the photo and the level of ‘patchiness’ is also exaggerated due to compression and processing of the image. As we explored earlier with respect to screen surface, the contrast is most impressive in a dimly lit room. Our observations below mainly relate to how things appear in dimmer lighting conditions. As the room becomes brighter, you’ll observe glare being diffused across the screen which creates a ‘hazing’ in front of the image. The monitor provided an exceptional contrast performance on Battlefield 2042. The per-pixel dimming and lack of ‘IPS glow’ or ‘VA glow’ provided an excellent atmosphere for darker scenes, with pleasing depth to dark shades. This also helped give a more defined look, with shadow details contrasting well with brighter elements – giving a nice ‘structure’ to various objects in the game, for example. The monitor also exhibited excellent gamma consistency, meaning that the depth of shades and detail levels were maintained evenly throughout the screen. There was some masking of dark detail due to the gamma tracking of our unit – not extreme and less noticeable than typical VA ‘black crush’, but still something that ideally wouldn’t be there. The exceptionally strong contrast provided benefits elsewhere, giving a definite solid look to medium shades which goes beyond the slightly translucent look LCDs can give them. The medium matte anti-glare screen surface provided less direct emission of light than some matte surfaces and certainly glossy surfaces. There was a moderate amount of graininess and layering in front of the image (we were quite aware of the screen surface, in other words) when observing lighter content. Similar contrast observations were made on Shadow of the Tomb Raider. This title includes many scenes with a few bright elements interspersed amongst much darker surroundings. The monitor provided the intended atmosphere here, with depth to darker shades maintained very well throughout the screen. With a bit of detail loss there due to the higher than ideal gamma for dark shades. The strong contrast helped give a more defined look to some objects and texture details, whilst brighter elements stood out nicely against darker surroundings. The screen surface again impeded the image more than some matte offerings, with moderate graininess observed for brighter content. We also watched the film Star Wars: The Rise of Skywalker. This looks its best on models with a strong contrast performance with bright flashes of light from explosions, flames and lightsabers against darker backgrounds. The monitor again gave exceptional depth and atmosphere here, though with some graininess and layering observed for lighter content and some detail masking for darker content. Also of note were the black bars at the top and bottom, as this film is presented in a letterboxed format. These bars appeared impressively deep and were therefore easy to ignore rather than becoming overly distracting or annoying. Most content you’d consume on streaming media platforms such as Netflix, Amazon Prime Video and Disney+ are presented without black bars. This is certainly the case for YouTube, too, where 16:9 content is standard. The Lagom tests for contrast allow specific weaknesses in contrast performance to be identified. The following observations were made in a dark room. The ASUS PG27AQDM’s colour gamut (red triangle) was compared with the sRGB (green triangle) and DCI-P3 (blue triangle) reference colour spaces using our ‘Test Settings’, as shown in the first image below. The gamut fully covers sRGB with significant extension beyond. We measured 97% DCI-P3 coverage using the SpyderX Elite, a bit below the 99% specified by the manufacturer. This coverage provides good potential for accurate output within the DCI-P3 colour space. The exact measured gamut can vary depending on measurement instrument and software, with slight inter-unit variation also possible. Although not shown in the graphic, we recorded 90% Adobe RGB coverage which isn’t high enough for accurate reproduction there regardless of calibration. This is a generous gamut which provides a good dose of extra vibrancy for standard sRGB content outside a colour-managed environment. The second image shows the gamut of the AW3423DW QD-OLED for comparison. The monitor also offers a highly flexible sRGB emulation setting, changing ‘Display Color Space’ to ‘sRGB’ in the ‘Color’ section of the OSD. This clamps the colour gamut close to sRGB, without restricting settings – you can adjust brightness, gamma and colour channels for example which is more than can be said for most sRGB emulation settings. Similar sRGB emulation is achieved by switching the ‘GameVisual’ mode to ‘sRGB’, but that is more restrictive as it locks off some settings including colour channels. Using this setting we recorded just a small amount of under-coverage (98% coverage) and a little over-extension in the red and blue regions. To maximise colour accuracy within the sRGB colour space, for colour-managed workflows, full calibration and profiling with a colorimeter or similar device is recommended. The generous DCI-P3 coverage would also make the monitor suitable for work within that wider colour space. You may try the ICC profiles featured in the calibration section which include various corrections including gamut mapping for colour-aware applications, but best results are always obtained by calibrating your own unit with your own hardware. Instead of using this ‘sRGB’ setting, AMD users can activate a flexible sRGB emulation setting via the graphics driver. This is done by opening ‘AMD Radeon Software’, clicking ‘Settings’ (cog icon towards top right) and clicking on ‘Display’. You should then ensure that the ‘Custom Color’ slider to the right is set to ‘Enabled’ and ‘Color Temperature Control’ set to ‘Disabled’. It may appear to be set this way by default, but the native rather than restricted gamut is likely in play. If that’s the case, simply switch the ‘Color Temperature Control’ slider to ‘Enabled’ then back to ‘Disabled’ to leverage the sRGB emulation behaviour. This setting is shown in the image below. The gamut below shows results using our ‘Test Settings’ with this driver tweak applied. The colour gamut covers 99% sRGB with just a sliver of extension beyond for the green to red edge. This setting offers excellent good tracking of sRGB and helps to cut down on the colour gamut without profiling, including in applications that aren’t colour managed. It also significantly reduced the blue channel and strengthened the green channel, giving a warm (~6100K) and somewhat green tint – a bit like a mild Low Blue Light (LBL) setting was applied. We’d recommend using the sRGB emulation setting of the monitor instead of this as it’s highly flexible, provides a broadly similar gamut and avoids significant GPU-level changes – these changes can slightly reduce shade variety and induce mild banding etc. Remember not to use this driver tweak under HDR or the image will appear significantly oversaturated. Whilst Nvidia doesn’t have a similar option in their graphics driver, a third party tool called ‘novideo_srgb’ can be used. This provides a similarly effective GPU-side gamut clamp to the AMD driver option. The resulting gamut was very similar to that shown above with the AMD tweak – this is expected given it uses the same data from the EDID of the monitor. The tool and its usage is covered in our sRGB emulation article. Colour output was vibrant on Battlefield 2042. As with most content viewed under SDR, either in-game or on the desktop, this title is developed around the sRGB colour space. Viewing such content on a monitor using a wider gamut than sRGB provides extra saturation and vibrancy – more than intended by the content creators. With a measured gamut mostly covering 97% DCI-P3, there’s certainly a good deal of extra saturation and vibrancy here. Red-biased shades such as earthy browns, woody tones and some skin tones appeared rather rich with a somewhat stronger than intended red hue. Some green shades also had extra punch to them and appeared overly vivid, though not as ‘neon’ as they might on models with more generous Adobe RGB coverage. The more constrained extension in the green to blue region, covering cyans, also meant that whilst sky blues were punchier than under sRGB, they didn’t appear cartoon-like with the level of saturation. Brightly painted objects of various colours in the game and roaring fires had a good level of vibrancy to them – though the flames verged more on the red (or reddish orange) side than intended. Similar observations were made on Shadow of the Tomb Raider. There was a vibrant look with significant extra saturation, but more constrained than on some models with an even more generous gamut. Woody and earthy tones plus some skin tones appeared with a red push and extra richness. Lara Croft, for example, appeared a touch sun-kissed though not to an extreme degree. Brightly painted artifacts, colourful flowers and berries in the game plus the reds, purples and blues of some of Lara’s dresses also looked vivid. There was also quite a lush look to vegetation with a nice variety of greens, though some shades appeared less muted than intended without appearing ‘neon’. If you want to tone things down and see things more as the developers intend, the gamut needs to be tamed – for example, by using the ‘sRGB’ mode of the monitor. As explored earlier this is effective in clamping the gamut closer to sRGB, curtailing saturation levels compared to the generous native gamut. Whether using this setting or not, excellent colour consistency was observed with very even saturation levels and shade representation throughout the screen. We made further observations whilst viewing the TV series Futurama. This is something of a torture test when it comes to colour consistency as there are large blocks of individual shade. As observed elsewhere, the monitor offered strong performance here. On VA and TN LCDs in particular, but even some IPS models, some shades will appear with significant shifts in saturation depending on the on-screen position. The consistency in this case was exceptional, without even minor shifts in that respect. Some very dark shades exhibited some minor striations, an issue explored earlier with respect to uniformity, but this was never extreme. The generous gamut provided good vibrancy, with various deep and neon shades (such as pinks, purples and yellows) appearing rather lively. Pastel shades were shown with excellent variety, but were more eye-catching than intended due to the gamut. sRGB emulation is again an option if you prefer things to look more muted and in-line with the original intentions for the content. The image below shows a printed reference sheet of 24 ‘sRGB’ shades, included as part of the Datacolor SpyderCHECKR 24 package. The screen is displaying reference photographs of this printed sheet, in both the same order as printed (right side) and reverse order (left side). The camera is mounted slightly above centre so that the image is representative of what the eye sees from an ergonomically correct viewing position. This, coupled with the inclusion of a flipped version of the shade sheet, allows both accuracy and colour consistency to be visually assessed. Bracketed numbers in our analysis refer to shades on the printed sheet or right side of the screen if they’re ordered consecutively from top left to bottom right. Interlaced lines visible in some places on the image are moiré from the camera, not observed on the monitor itself. Note that there is always some disparity between how emissive objects (monitor) and non-emissive objects (printed sheet) appear. The monitor is set to a very low brightness to help minimise this disparity. The representation of shades in this image depends on the camera and your own screen, it’s not designed to show exactly how the shades appear in person. It still helps demonstrate some of the relative differences between the original intended sRGB shade and what the monitor outputs, however. Full profiling and appropriate colour management on the application would provide a tighter match, our intention here is to show what can be expected in a non colour-managed environment. Lagom’s viewing angle tests help explore the idea of colour consistency and viewing angle performance. The following observations were made from a normal viewing position, eyes ~70cm from the screen. On some monitors, particularly but not exclusively those with high refresh rates, interlace patterns can be seen during certain transitions. We refer to these as ‘interlace pattern artifacts’ but some users refer to them as ‘inversion artifacts’ and others as ‘scan lines’. They may appear as an interference pattern, mesh or interlaced lines which break up a given shade into a darker and lighter version of what is intended. They often catch the eye due to their dynamic nature, on models where they manifest themselves in this way. Alternatively, static interlace patterns may be seen with some shades appearing as faint horizontal or vertical bands of a slightly lighter and slightly darker version of the intended shade. We did not observe either artifact type on this monitor. A sensitive camera and a utility called SMTT 2.0 was used to analyse the latency of the PG27AQDM. Over 30 repeat readings were taken to help maximise accuracy. Using this method, we calculated 1.12ms (slightly over 1/4 of a frame at 240Hz) of input lag. This figure is influenced primarily by the main element of input lag you ‘feel’ (signal delay) and indicates a very low signal delay which shouldn’t bother even sensitive users. Due to the extremely rapid pixel responses, the element of input lag you ‘see’ (pixel responsiveness) only contributes in a very minor way to this figure. Note that we don’t have the means to accurately measure input lag with VRR technology active in a VRR environment or HDR active in an HDR environment. Our article on responsiveness explores the key factors surrounding monitor responsiveness. A key concept explored is ‘perceived blur’, contributed to by both the pixel responses of the monitor and the movement of your eyes as you track motion on the screen. Both factors are important, though the second factor is dominant on modern monitors. The article also explores a photography technique called ‘pursuit photography’, which uses a moving rather than stationary camera to capture motion in a way that reflects both elements of perceived blur rather than just the pixel response element. The images below are pursuit photographs taken using the UFO Motion Test for ghosting, with the test running at its default speed of 960 pixels per second. This is a good practical speed to take such photographs at and highlights both elements of perceived blur well. The UFOs move across the screen from left to right at a frame rate matching the refresh rate of the display. All three rows of the test are analysed to highlight a range of pixel transitions. The monitor was tested at 60Hz (directly below), 120Hz and 240Hz. The final columns show reference screen set to what we consider its optimal response time setting (where applicable) for a given refresh rate. This first reference screen is the Dell Alienware AW3423DW with QD-OLED panel. The second is the Gigabyte AORUS FI27Q-X, which is a competent 240Hz IPS performer. At 60Hz, above, the UFO appears soft and unfocused without clear internal detailing. This reflects a moderate amount of perceived blur due to eye movement. Unlike the IPS reference screen, there are no visible weaknesses from slower than optimal pixel responses. These weaknesses are apparent on the FI27Q-X mainly as ‘powdery’ trailing behind the UFOs, but there’s not even a trace of that on the ASUS or the QD-OLED reference. Because these models use natively fast OLED panels, they don’t require aggressive overdrive to achieve exceptional pixel responsiveness and therefore no overshoot (inverse ghosting) is perceived. You can see a slight red fringe towards the left of the yellow UFO cockpit for the dark background (top row), which is more noticeable in the images at higher refresh rates but very difficult to spot by eye with the UFO in motion. This is not overshoot but is instead related to the subpixel layout as highlighted earlier in the review. The images below show things with refresh rate doubled to 120Hz. The FI27Q-X is running at 144Hz as pursuit photos were not taken at 120Hz. Pixel response behaviour did not vary significantly between those refresh rates, however. At 120Hz, above, the UFO appears significantly narrower with clearer internal detail. This reflects a significant decrease in perceived blur due to eye movement. The UFO segmentation and separating black lines were clearer to the eye than they appear on the photos. The pixel response requirements are significantly increased here and some weaknesses can be observed on the LCD reference screen. The ‘powdery’ trailing is now more pronounced, particularly for the dark background (top row). The PG27AQDM, on the other hand, presents exceptional 120Hz sample and hold motion clarity without any weaknesses related to the pixel responses. The QD-OLED reference performs similarly – and there is again no perceivable overshoot on the ASUS or the QD-OLED reference. The clarity appears superior on the ASUS compared to the AW3423DW in the photo, but we ran them side by side and could confirm that visually they were extremely similar to one another and closer to what is shown in the PG27AQDM photo. That’s because the camera settings were better optimised when taking the ASUS photo than the Alienware. Below you can see things with refresh rate doubled again to 240Hz. At 240Hz, above, the UFO appears significantly narrower with significantly improved definition. This reflects another significant reduction in perceived blur due to eye movement. The pixel response requirements for a strong performance are greatly increased, so the ‘powdery trailing’ for the LCD reference screen is more noticeable now. In the case of the ASUS, there are no observable weaknesses – a visually flawless sample and hold 240Hz performance. The UFO segmentation is again more distinct than it appears in the photo and also more distinct than at 120Hz. The white notches on the UFO body are easy to count as well, more distinct than they appear in the photo. These sorts of small details appear more blended on sample and hold LCDs, even on LCDs with superior pixel responsiveness to the FI27Q-X. On various Battlefield titles, with a frame rate keeping up with the 240Hz refresh rate, the monitor gave an exceptionally responsive and visually fluid experience. With the screen outputting up to 4 times as much visual information every second as a 60Hz monitor or this monitor running at 60Hz (or 60fps). This significantly enhanced ‘connected feel’, which describes the precision and fluidity you feel when interacting with the game world. The very low input lag also aided this. The combination of high frame and refresh rate also decreases perceived blur due to eye movement, as demonstrated earlier using Test UFO. This can provide a nice competitive edge for gaming (especially when combined with rapid pixel responses) and can potentially enhance viewing comfort. The benefits in terms of ‘connected feel’ and reduced perceived blur compared to the 120Hz (120fps) experience were also appreciated. Perhaps less ‘game-changing’ for some as the initial boost from 60Hz (60fps) to 120Hz (120fps) but still something we readily noticed and some will really appreciate. Although more minor, both mathematically and visually, we still appreciated the increase from the 175Hz on the AW3423DW to 240Hz on this model. Even relatively fast LCDs such as the FI27Q-X used as a reference earlier have some weaknesses due to slower than optimal pixel responses, giving ‘powdery’ trailing in places that slightly increases perceived blur. And even the fastest LCDs, such as the BenQ ZOWIE XL2566K, have some weaknesses when it comes to transitions involving bright shades. For example lights in a game, brightly painted sections of a building, specular highlights (i.e. light reflections on shiny surfaces), name tags etc. There’s also some overshoot to contend with for quite a range of transitions including ‘halo’ trailing that’s slightly brighter than the background and ‘dirty’ trailing that’s a bit darker than the background. These are due to the pixel overdrive required to accelerate those pixel transitions. The PG27AQDM’s OLED panel provides no perceivable weaknesses whatsoever from its pixel transitions, aiding the visual fluidity and helping it deliver the most you can expect out of its 240Hz sample and hold refresh rate. Even minor details in the game world remained relatively sharp during motion when compared to a sample and hold LCD of even a higher refresh rate, including intricate bright and dark details. The monitor doesn’t include a strobe backlight setting (or in this case pixel strobing or ‘Black Frame Insertion’ – BFI), which would work to really minimise perceived blur due to eye movement. We’re sure some would’ve liked to see such an option here as the exceptionally fast pixel responses can lend themselves very well to such an operating mode. We also observed video content at a range of refresh rates, including ~24 – 30fps content on platforms such as Netflix, Disney Plus and Amazon plus 60fps content on YouTube. Because of the essentially instantaneous pixel responses, there is not even the most minor mask of additional perceived blur for any of this movie content. As such you become quite aware of the limited frame rate, observing ‘low framerate judder’ in quite a clear fashion for example. Because 24fps, 30fps and 60fps divides evenly into the 240Hz refresh rate of the screen, judder is reduced somewhat compared to where there isn’t an even (or nearly even) division. Though the low frame rate itself is not changed and is a key barrier to fluidity. If Adaptive-Sync is used, it will automatically adjust the refresh rate to match the frame rate of some full screen video content. As an Amazon Associate I earn from qualifying purchases made using the below link. Where possible, you’ll be redirected to your nearest store. Further information on supporting our work. AMD FreeSync is a variable refresh rate technology, an AMD-specific alternative to Nvidia G-SYNC. Where possible, the monitor dynamically adjusts its refresh rate so that it matches the frame rate being outputted by the GPU. Both our responsiveness article and the G-SYNC article linked to explore the importance of these two elements being synchronised. At a basic level, a mismatch between the frame rate and refresh rate can cause stuttering (VSync on) or tearing and juddering (VSync off). FreeSync also boasts reduced latency compared to running with VSync enabled, in the variable frame rate environment in which it operates. FreeSync requires a compatible AMD GPU such as the Radeon RX 580 used in our test system. The monitor itself must support ‘VESA Adaptive-Sync’ for at least one of its display connectors, as this is the protocol that FreeSync uses. The PG27AQDM supports FreeSync Premium via DP and HDMI on compatible GPUs and systems. Note that HDR can be activated at the same time as FreeSync. You need to make sure ‘Adaptive-Sync’ (DP) or ‘Variable Refresh Rate’ (HDMI) is enabled in the ‘Gaming’ section of the OSD. On the GPU driver side recent AMD drivers make activation of the technology very simple. You should ensure the GPU driver is setup correctly to use FreeSync, so open ‘AMD Software’, click ‘Settings’ (cog icon towards top right) and click on ‘Display’. You should then ensure that the first slider is set to ‘Enabled’ as shown below. The top image shows the monitor connected by DP and the bottom image by HDMI. The setting is referred to as ‘AMD FreeSync Premium’ in both cases, although the exact wording may depend on the driver version you’re using. To configure VSync, open ‘AMD Software’. Click ‘Settings’ (cog icon towards top right) and click ‘Graphics’. The setting is listed as ‘Wait for Vertical Refresh’. This configures it globally, but if you wish to configure it for individual games click ‘Game Graphics’ towards the top right. The default is ‘Off, unless application specifies’ which means that VSync will only be active if you enable it within the game itself, if there is such an option. Such an option does usually exist – it may be called ‘sync every frame’ or something along those lines rather than simply ‘VSync’. Most users will probably wish to enable VSync when using FreeSync to ensure that they don’t get any tearing. You’d therefore select either the third or fourth option in the list, shown in the image below. Above this dropdown list there’s a toggle for ‘Radeon Enhanced Sync’. This is an alternative to VSync which allows the frame rate to rise above the refresh rate (no VSync latency penalty) whilst potentially keeping the experience free from tearing or juddering. This requires that the frame rate comfortably exceeds the refresh rate, not just peaks slightly above it. We won’t be going into this in detail as it’s a GPU feature rather than a monitor feature. As usual, we tested a range of game titles using AMD FreeSync and the experience was very similar in all cases. Issues affecting one title but not others would point towards a problem with the game or GPU driver rather than the monitor. For simplicity we’ll just focus on Battlefield titles in this section. There’s sufficient flexibility with the graphics options to allow the full VRR range to be analysed on our Radeon RX 580. This is by no means a powerful GPU, so frequent dips below 240fps occur even with heavily reduced graphics settings. Without a VRR technology such as FreeSync active you get a mismatch between the frame and refresh rate which causes stuttering (VSync on) or tearing (VSync off). With FreeSync synchronising things appropriately, such issues are eliminated – very welcome if you’re sensitive to tearing and stuttering. Drops in frame rate still reduce the ‘connected feel’ and increase perceived blur due to eye movement, however. Monitors with particularly strong contrast are prone to flickering for some shades during heavy frame rate fluctuations. These are due to slight gamma changes at the lower end of the curve as refresh rate changes in a VRR environment and are not visible on models with relatively weak contrast. We observed some flickering under VRR for dark and medium-dark shades, mainly during heavy frame rate fluctuation. We’ve seen some refer to this as “near-black flickering”, but we find that a bit misleading as it can also be observed for medium-dark shades that aren’t particularly “near-black” as well. If your GPU is relatively powerful it may be the case that this is not commonly observed during regular gameplay due to the frame rate staying relatively high and stable. But you may observe this for some darker scenes or content where there are sufficient drops and fluctuations in frame rate. It could also be observed quite readily during certain loading screens or some in-game menus where frame rate fluctuated heavily. It was not as obtrusive as the more intense and widespread flickering common to VA models, which are not only related to gamma changes but also high voltage sensitivity in a VRR environment. We did find it a bit more noticeable and intense compared to the AW3423DW, so it seems the G-SYNC module does perform at least some degree of gamma compensation under VRR. If you do find it bothersome it might be worthwhile limiting frame rate to limit fluctuations, or simply forgoing VRR altogether and sticking to a static refresh rate such as 240Hz. On LCD monitors with Adaptive-Sync, we’d typically mention a lack of effective variable overdrive, meaning increasingly strong overshoot can be observed as refresh rate decreases – and advising users to switch over to a lower overdrive setting as a result. As typical for an OLED screen it isn’t an issue here. As we explored with respect to Test UFO (and this holds true with VRR active, throughout the entire VRR range) the panel is natively extremely fast and doesn’t require the same sort of pixel overdrive as LCDs. FreeSync worked down to the floor of operation, which in our testing was usually ~46Hz (46fps), below which LFC (Low Framerate Compensation) kicked in. LFC keeps the refresh rate at a multiple of the frame rate to keep tearing and stuttering at bay. There was a reasonably subtle momentary stuttering when LFC activated or deactivated, something we always observe and not specific to this model. It was somewhat more noticeable in this case given the exceptional pixel responsiveness, which didn’t add even the slightest mask of additional perceived blur. But it remained much less noticeable than traditional stuttering from frame and refresh rate mismatches – if you’re sensitive to it and frequently passing the boundary it could be annoying, but otherwise it shouldn’t be an issue. The sudden and significant change in refresh rate as LFC activates or deactivates can also induce VRR flickering. As noted earlier, AMD FreeSync makes use of Adaptive-Sync technology on a compatible monitor. As of driver version 417.71, users with Nvidia GPUs (GTX 10 series and newer) and Windows 10 or later can also make use of this Variable Refresh Rate (VRR) technology. When a monitor is used in this way, it is something which Nvidia refers to as ‘G-SYNC Compatible’. The ASUS is amongst models which are specifically validated as G-SYNC compatible, which means it has been tested by Nvidia and passes specific quality checks. With the PG27AQDM you can connect the monitor up using DisplayPort or HDMI to use ‘G-SYNC Compatible Mode’. You need to make sure ‘Adaptive-Sync’ (DP) or ‘Variable Refresh Rate’ (HDMI) is switched on in the ‘Gaming’ section of the OSD to use the technology. When you open up Nvidia Control Panel, you should then see ‘Set up G-SYNC’ listed in the ‘Display’ section. Ensure the ‘Enable G-SYNC, G-SYNC Compatible’ checkbox and ‘Enable settings for the selected display model’ is checked as shown below and press ‘OK’. If you’ve enabled ‘G-SYNC Compatible’ and it was previously disabled, the monitor should re-establish its connection with the system and the technology should now be active. HDMI 2.1 includes Variable Refresh Rate (VRR) support as part of the specification. This is an integrated technology, which unlike FreeSync does not rely on VESA Adaptive-Sync to function. Although this monitor is advertised as having HDMI 2.0, based on available bandwidth, it includes some of the HDMI 2.1 optional features including VRR. You need to ensure ‘Variable Refresh Rate’ is set to ‘ON’ in the ‘Gaming’ section of the OSD to use the technology. This feature can be used by devices such as the PS5 that don’t support Adaptive-Sync. It can also be leveraged via ‘G-SYNC Compatible Mode’ on compatible Nvidia GPUs. Based on our testing of ‘G-SYNC Compatible Mode’ using HDMI 2.1 VRR, the experience was very similar to the Adaptive-Sync experience under SDR and HDR. On an ideal monitor, HDR (High Dynamic Range) involves the simultaneous display of very deep dark shades and brilliantly bright light shades. As well as a vast array of shades between these extremes, including muted pastel shades alongside very vibrant saturated shades. Ideally, per-pixel illumination would be provided (e.g. self-emissive displays such as this), or for LCDs a very large number of precisely controlled dimming zones used. A solution such as FALD (Full Array Local Dimming) with a generous number of dimming zones, for example. Such a solution would allow some areas of the screen to remain very dim whilst others show brilliantly high brightness. Colour reproduction is also an important part of HDR, with the ultimate goal being support for a huge colour gamut, Rec. 2020. A more achievable near-term goal is support for at least 90% DCI-P3 (Digital Cinema Initiatives standard colour space) coverage. Finally, HDR makes use of at least 10-bit precision per colour channel, so its desirable that the monitor supports at least 10-bits per subpixel. HDR10 is the most widely supported standard used in HDR games and movies and what is supported here. For games and other full screen applications that support HDR, the ASUS PG27AQDM automatically switches to its HDR operating mode if an HDR signal is provided. Some game titles will activate HDR correctly when the appropriate in-game setting is selected. Others that support HDR will only run in HDR if ‘Use HDR’ is turned on in Windows, too. Related Windows HDR settings are found in the ‘Windows HD Color settings’ (Windows 10) or ‘HDR’ (Windows 11) section of ‘Display settings’ (right click the desktop). If you want to view HDR movie content, ensure ‘Stream HDR Video’ (Windows 10) or ‘Play streaming HDR video’ (Windows 11) is active. Also note that there’s an ‘HDR/SDR brightness balance’ (Windows 10) or ‘SDR content brightness’ (Windows 11) slider that allows you to adjust the overall balance of SDR content if HDR is active in Windows. This is really just a digital brightness slider that only makes changes for SDR content. The gamma behaviour and colour output for SDR content isn’t quite right, regardless of how you set this up. Coupled with the restrictions you have in terms of adjustability in the OSD, we’d only recommend activating HDR in Windows if you’re about to use an HDR application that specifically requires it. To keep things simple, we’ll primarily focus on Shadow of the Tomb Raider for this section, though a range of games were tested. This is a title we’ve used on a large number of monitors under HDR, with varying capabilities, and we know it provides a good test for HDR on the hardware side. Although our testing here focuses on HDR PC gaming using DisplayPort, with an Nvidia RTX 3090, similar observations were made when viewing HDR video content using the Netflix app. As with games, some of this content makes better use of HDR than other content. There are a few additional points to bear in mind if you wish to view HDR video content like this. We also made similar observations using HDMI, which would be used when viewing HDR content on an HDR compatible games console for example. Testing on both our Nvidia and AMD GPUs showed that the HDR implementation was similar in both cases, too. Under HDR there are three ‘HDR Setting’ modes; ‘HDR Gaming’, ‘HDR Cinema’ and ‘HDR Console’. In our testing these settings were indistinct from one another and provided exactly the same output – whether observing the desktop (SDR content), games, Netflix or YouTube video content under HDR on our PC. This could potentially change depending on firmware or perhaps if a system such as games console is detected instead of a PC. The other setting of note is ‘Color Temp.’ which can be set to ‘6500K’ or ‘8200K’. As explored earlier the ‘8200K’ setting gives a bit of a boost to brightness, but not enough in our opinion to offset the cool and icy look plus potentially increased visual fatigue. So we stuck to ‘6500K’, which gave a more natural look to things. Another setting of potential interest is ‘Brightness Adjustable’, which can be activated in any of the ‘HDR Setting’ modes. The ‘Brightness Adjustable’ setting, as the name implies, allows brightness to be adjusted according to taste. The monitor alerts you that adjusting the brightness under HDR will alter the PQ Curve. The monitor’s HDR is calibrated for brightness at ‘100’ and things are not neatly mapped to lower brightness levels, so if you reduce brightness you gain a duller look with many shades appearing washed out (as if gamma is too low under SDR) as a result. Controls including brightness (unless ‘Brightness Adjustable’ is active), gamma and colour channels are locked off. Whilst firmware tweaking may be able to provide some further refinement to HDR colour output, there are certain physical limitations in place as well. Some models provide a much wider colour gamut covering more of Adobe RGB and therefore also more of the Rec. 2020 colour space. This would include models like the Acer XB323U GP and ASUS PG32UQX with QD Mini LED backlights. The extension in the blue to green edge of the gamut (also covering cyans) is less extreme on the PG27AQDM, curtailing the vibrancy of some brightly painted objects, sky blues and some forest vegetation for example. The QD-OLED panel used in the likes of the AW3423DW offers more extension in various regions of the gamut compared to the WOLED panel. The use of an unfiltered white subpixel to assist with high brightness output on the PG27AQDM also reduces colour volume, meaning saturation is reduced at the increased brightness levels that are common for some elements under HDR. Brightly illuminated golden objects, lava and embers for example appeared less intensely saturated than we’ve seen, including on the Alienware AW3423DW. Bright and strongly saturated particles such as the spell effects, energy pulses and some neon lights in games are other examples of elements which highlight this difference in colour volume. Bright elements tended to appear pastel without the intended saturation levels. And some very bright elements appeared to have a bright and pure white core with a dimmer but more colourful surrounding. Like a sort of posterization effect, rather than showing a more blended mixture of bright and saturated shades. The monitor also supports 10-bit colour, which can be used efficiently for HDR10 content like this to facilitate the enhanced luminance and shade mapping precision expected under HDR. It helps the monitor put its wide gamut to good use and also enhances the nuanced shade variety. At the low end, for example, there’s a natural uplift in detail due to the superior range of dark shades. This is very different to what could be achieved with a gamma enhancement under SDR, where things appear artificially brightened up and potentially ‘flooded’ or ‘blocky’ in places. There was less masking of dark detail than we observed under SDR and less than on most Mini LED models which lack the same luminance precision (‘dimming zone’ count) – but a bit more masking than we observed on the AW3434DW. Some medium shades were a bit deeper than they should be as well, dulling some elements in certain scenes slightly. The 10-bit precision also allows the monitor to output a greater range of closely matching bright shades, which smooths out gradients and provides more natural progressions for elements such as smoke, weather and particle effects. The image below shows one of the scenes we particularly like from Shadow of the Tomb Raider under HDR. Remember that the photo is purely for illustrative purposes and in no way represents how the monitor appeared running HDR in person. In this scene there are some nice eye-catching bright elements such as the glint of light on the water surface and light streaming in from above. Though the light glint on the water showed the posterization effect noted earlier with multiple distinct layers – this particular element should appear as a blended warm white with an even warmer surrounding ridge rather than appearing with so many distinct layers. The brightness of these elements meant they weren’t as eye-catching as we’ve seen on some Mini LED models, but were still nice and bright and largely similar to what we observed on the AW3423DW. As our measurements earlier in the review showed, as brighter shades dominate the ABL (Automatic Brightness Limiter) kicks in and dims things significantly. This doesn’t just affect the bright shades, it applies universally and dims HUD elements and various medium shades as well. This applied to some extent in the scene as shown above, but was more noticeable if Lara was repositioned so the light streaming in from the sky fills up most of the screen. In practice there were certainly some scenes on this game and indeed other titles that show a sufficient amount of bright content for this to occur, but many scenes where the monitor is able to provide good strong bursts of brightness closer to the peak we recorded earlier (926 nits). The per-pixel illumination helped even intricate details such as rock cracks and shadowy patches of vegetation appear relatively well-defined, though some of this detail was still a bit more masked than it could be given the per-pixel illumination. It also injected extra depth to medium shades, giving them a very solid look. The precision was very helpful in scenes where very bright and dark shades closely intermingled – glowing embers and torches surrounded by darkness being a good example. There was no ‘haloing’ to worry about at the boundary between the very bright and much darker shades as exhibited by current Mini LED backlights. The section of video review below explores the HDR performance of the monitor using various scenes from Shadow of the Tomb Raider, Cyberpunk 2077 and Battlefield V. It may be desirable or perhaps necessary to run the monitor below its native 2560 x 1440 (QHD or 1440p) resolution. For performance reasons, or because you’re using a system (such as a games console) that doesn’t support a QHD signal. The monitor provides scaling functionality via both DP and HDMI. It can be run at resolutions such as 1920 x 1080 (Full HD) and can use an interpolation (scaling) process to map the image onto all pixels of the screen. This is supported at all listed refresh rates. As explored earlier the monitor also includes a 3840 x 2160 (‘4K’ UHD) downsampling mode, allowing it to output a ‘4K’ UHD signal at up to 60Hz. To ensure the monitor rather than GPU is handling the scaling process, as a PC user, you need to ensure the GPU driver is correctly configured so that the GPU doesn’t take over the scaling process. For AMD GPU users, the driver is set up correctly by default to allow the monitor to interpolate where possible. Nvidia users should open Nvidia Control Panel and navigate to ‘Display – Adjust desktop size and position’. Ensure that ‘No Scaling’ is selected and ‘Perform scaling on:’ is set to ‘Display’ as shown in the following image. As usual, if you’re running the monitor at 2560 x 1440 and viewing lower resolution content (such as a 1920 x 1080 Full HD video) then it is the GPU and software that handles the upscaling. That’s got nothing to do with the monitor itself – there is a little bit of softening to the image compared to viewing such content on a native Full HD monitor, but it’s not extreme and shouldn’t bother most users. The video below shows the monitor in action. The camera, processing done and your own screen all affect the output – so it doesn’t accurately represent what you’d see when viewing the monitor in person. It still provides useful visual demonstrations and explanations which help reinforce some of the key points raised in the written piece. With its 26.5” QHD OLED panel and 240Hz refresh rate, the ASUS ROG Swift OLED PG27AQDM is well-positioned as a gaming monitor. The pixel density is decent enough to provide a good level of detail in games, without being as demanding as ‘4K’ UHD. The latter is ‘supported’ mainly with games consoles in mind by way of a downsampling mode, though this is limited to 60Hz due to the monitor lacking HDMI 2.1 (despite including some of its features, such as integrated VRR support). The monitor offers a feature-rich OSD with fully flexible (non-restricted) sRGB emulation mode, though for HDR is very limited in the adjustment that can made. The monitor offers distinct and potentially divisive ROG styling, with a very solid coated metal stand, an exceptionally slender main screen area from a side profile and a few customisable lighting features. The most interesting and attractive of which, in our view, faces the wall and is not appreciated from the front. The ergonomic flexibility of the screen is also strong with a fully adjustable stand – using the included VESA support will also remove a lot of the ‘gamery’ styling from the front, if it’s not to your taste. Exceptional contrast was provided, particularly in dimmer conditions. Being able to deliver ~250 nits regardless of content displayed under SDR without normal ABL behaviour (using the ‘Uniform Brightness’ setting) and strong glare handling from the screen surface will appeal to some. Though the screen surface also impeded the clarity and vibrancy potential compared to lighter matte and glossy offerings. The gamma tracking was also a bit wonky at both the low and high ends, masking dark detail a bit and making closely matched very bright shades less distinct than ideal. These weren’t major impediments to the overall contrast experience, in our view, and less obtrusive than the shortcomings of any LCD panel type when it comes to contrast. The monitor offered strong HDR brightness output which complemented the per-pixel illumination of the OLED panel well, with the usual caveat of ABL kicking in where bright shades dominate. Because of the subpixel layout and inclusion of an unfiltered white subpixel, the screen was not able to offer appropriate saturation to bright shades. Colourful bright shades appeared too pastel and some posterization was observed for the brightest shades with an abrupt transition between bright white core and more colourful surrounding layers. This subpixel layout was also far from ideal on the desktop, due to fringing issues. The monitor delivered excellent colour consistency and strong SDR vibrancy, with the highly flexible sRGB mode an option if you want to tone that down. For HDR the monitor was able to put its generous DCI-P3 coverage to fairly good use. There were inaccuracies which meant some shades were a bit undersaturated or slightly muddy-looking and others were slightly oversaturated, but we don’t consider these major issues that will jump out at most people when viewing the monitor in isolation. The overall look was still vibrant but appropriate overall, without the oversaturated look of using the full gamut under SDR. The monitor offered a brilliantly fluid 240Hz experience, with exceptionally low input lag and outstanding pixel responsiveness without perceivable overshoot. Yes, it’s a monitor worthy of some superlatives in that department. The monitor also offered VRR which worked as expected on our AMD and Nvidia GPUs, with integrated ‘HDMI 2.1 VRR’ support also provided. VRR flickering was observed during significant fluctuations in frame rate, which is always expected to some degree on OLED models. But reduced refresh rates weren’t accompanied by any perceivable overshoot – just a perfectly rapid pixel responsiveness which gave as little perceived blur as you can expect from a sample and hold monitor at a given refresh rate. A BFI or pixel strobing option wasn’t included to help break free from the sample and hold limitations, however. Given the performance characteristics of the OLED panel, any comparison with a 240Hz QHD LCD would really be apples to oranges. There are various alternatives either available or to be released shortly after this one which share the panel. A key competitor is the LG 27GR95QE which includes full HDMI 2.1 functionality, hardware calibration and a remote for convenient OSD operation. Test data we’ve seen so far suggests it can’t reach the same brightness under HDR – we’ll reserve any further points of comparison for our review of that model. It’s also worth comparing to the QD-OLED models, such as the Dell Alienware AW3423DW we have considerable experience with and used to draw various comparisons throughout the review. The Alienware includes the superior warranty, with ‘burn in cover’ specifically included in the 3 year warranty. As noted in our fringing article, we found the QD-OLED fringing less noticeable than on the WOLED panel. Outside of this the QD-OLED ultrawides offer a more immersive experience due to their extra width, with superior horizontal ‘desktop real estate’ as well. They also have a more generous colour gamut and glossy screen surface, offering superior vibrancy – though the ASUS can also deliver a very good level of vibrancy and some may prefer the matte screen surface. Due to the differences in screen surface, gamut and reduced colour volume at high brightness (plus to a lesser extent HDR calibration) we found the HDR more impressive and impactful on the Alienware. With superior ‘pop’ to bright saturated shades and a generally richer look in mixed scenes. The G-SYNC module provided a bit of a smoother VRR experience on the Alienware as well, though that’s not something everyone would be sensitive enough to notice. When it comes to a mixture of gaming, including some competitive, we certainly appreciated the exceptionally fluid and low input lag 240Hz OLED experience offered by the PG27AQDM. Combine this with the exceptional OLED contrast and colour consistency plus the more compact and ‘competitive gamer friendly’ 27” screen size – and you’re left with the sort of experience some will really love. As an Amazon Associate I earn from qualifying purchases made using the below link. Where possible, you’ll be redirected to your nearest store. Further information on supporting our work.
The SpyderX Elite was used to assess the uniformity of lighter shades, represented by 9 equally spaced white quadrants running from the top left to bottom right of the screen. The table below shows the luminance recorded at each quadrant as well as the percentage deviation between each quadrant and the brightest recorded point.
Luminance uniformity table
Luminance uniformity map
Colour temperature uniformity map
Contrast in games and movies
Lagom contrast tests
Colour reproduction
Colour gamut
Colour gamut 'Test Settings'
Colour gamut QD-OLED (AW3423DW)
Colour gamut 'sRGB'
Colour gamut AMD 'CTC disabled'
Colour in games and movies
Shade representation using SpyderCHECKR 24
The monitor presents colours in a vibrant way, with most shades showing at least some degree of oversaturation due primarily to the colour gamut. Medium orange (3), Persian pink (6) – more so than it appears in the photo, lemon yellow (10), Tango pink (11) and candy apple red (14) look quite a bit more vivid than intended. Gamboge (23) also appears with too much of a saffron tint whilst peach pink (20) and light chocolate brown (24) show a bit of a red push. Dark lime green (18) and yellow green (19) appear a bit eye-catching as well, though this oversaturation is less extreme than on models with more generous Adobe RGB coverage. The colour consistency is strong, though, without the clear saturation shifts you’d observe on VA or TN models depending on the on-screen shade position. Some of the discrepancies here are due to slight uniformity issues on our unit or slight extra glare at some points. Illuminating the printed sheet properly whilst entirely avoiding glare on the screen is challenging. The image below shows how things appear using the sRGB emulation mode (‘Display Color Space’ set to ‘sRGB’ with factory defaults under ‘Racing Mode’).
Saturation levels are significantly reduced now, with a more appropriate representation to most shades. Medium orange (3) appears slightly undersaturated and so does gamboge (23), appearing with too little of a golden tone. Cerulean (2) and aquamarine (4) appear too cool and blue-biased with a slightly weak green component – this is not entirely down to the slightly high white point (can be corrected), though that contributes to an extent. Most remaining shades are outputted accurately. As usual, we’d recommend profiling the monitor with your own colorimeter or spectrophotometer if you require the highest level of colour accuracy.
Viewing angles
The video below shows the Lagom text test, a mixed desktop background, game scene and dark desktop background from various viewing angles. The shifts in the image including contrast, colour and the representation of black are extremely minor. Performance here is much stronger than on any LCD we’ve observed and almost looks like you’re viewing a picture rather than a screen due to the strong consistency here.
Interlace pattern artifacts
Responsiveness
Input lag
Perceived blur (pursuit photography)
Responsiveness in games and movies
VRR (Variable Refresh Rate) technology
FreeSync – the technology and activating it
The ASUS supports a variable refresh rate range of 40 – 240Hz (40 – 120Hz via HDMI at native QHD resolution). That means that if the game is running between 40fps and 240fps, the monitor will adjust its refresh rate to match. When the frame rate rises above 240fps, the monitor will stay at 240Hz and the GPU will respect your selection of ‘VSync on’ or ‘VSync off’ in the graphics driver. With ‘VSync on’ the frame rate will not be allowed to rise above 240fps, at which point VSync activates and imposes the usual associated latency penalty. With ‘VSync off’ the frame rate is free to climb as high as the GPU will output (potentially >240fps). AMD LFC (Low Framerate Compensation) is also supported by this model, which means that the refresh rate will stick to multiples of the frame rate where it falls below the 40Hz (40fps) floor of operation for FreeSync. If a game ran at 32fps, for example, the refresh rate would be 64Hz to help keep tearing and stuttering at bay. LFC usually activated at a slightly higher refresh rate of 46Hz or just slightly below – this slightly different floor of operation makes little difference in practice. This feature is used regardless of VSync setting, so it’s only above the ceiling of operation where the VSync setting makes a difference.
Some users prefer to leave VSync enabled but use a frame rate limiter set a few frames below the maximum supported (e.g. 237fps) instead, avoiding any VSync latency penalty at frame rates near the ceiling of operation or tearing from frame rates rising above the refresh rate. If you activate the ‘FPS Counter’ feature in the ‘GamePlus’ section of the OSD, the refresh rate will be displayed on the screen. This will reflect the frame rate if it’s within the main VRR window. The final point to note is that FreeSync only removes stuttering or juddering related to mismatches between frame rate and refresh rate. It can’t compensate for other interruptions to smooth game play, for example network latency or insufficient system memory. Some game engines will also show stuttering (or ‘hitching’) for various other reasons which won’t be eliminated by the technology.
FreeSync – the experience
Nvidia Adaptive-Sync (‘G-SYNC Compatible’)
On this page of the graphics driver it states: “Selected Display is not validated as G-SYNC Compatible.” This means Nvidia hasn’t specifically tested and validated the display, not that it won’t work. On our RTX 3090 the experience was very similar to what we described with FreeSync. With the technology getting rid of tearing and stuttering from what would otherwise be frame and refresh rate mismatches, within the VRR range. Similar VRR flickering behaviour was observed, mainly with heavy fluctuations in frame rate and hence refresh rate. An LFC-like frame to refresh multiplication technology was employed below that to keep tearing and stuttering from frame and refresh rate mismatches at bay, though this seemed to activate ~50Hz which is slightly higher than on the AMD side. This doesn’t make a lot of difference in practice, unless your frame rate happens to be hovering around very specific values either side of this. There was again a reasonably subtle momentary stuttering and potential flickering as the boundary was crossed, as we observed with our AMD GPU as well. Our suggestions regarding use of VSync also apply, but you’re using Nvidia Control Panel rather than AMD Software to control this. The setting is found in ‘Manage 3D settings’ under ‘Vertical sync’, where the final option (‘Fast’) is equivalent to AMD’s ‘Enhanced Sync’ setting. You’ll also notice ‘G-SYNC Compatible’ listed under ‘Monitor Technology’ in this section, as shown below. Make sure this is selected (it should be if you’ve set everything up correctly in ‘Set up G-SYNC’).
Note again that you can activate the ‘FPS Counter’ feature in the ‘GamePlus’ section of the OSD. This will display the refresh rate of the display and therefore indicates the frame rate if that is within the VRR window (~50 – 240Hz). This is a useful indication that the technology is active. And as with AMD FreeSync Premium, HDR can be used at the same time as ‘G-SYNC Compatible’.
HDMI 2.1 VRR
HDR (High Dynamic Range)
Colour gamut 'Test Settings'
As a reminder, we recorded 97% DCI-P3 coverage with very little extension beyond the gamut. This is shown in the image above with a red triangle showing the monitor, blue triangle DCI-P3 and green triangle sRGB. This coverage combined with the very strong colour consistency and contrast performance allowed the monitor to deliver a decent dose of vibrancy where intended by the developers, such as brightly painted objects and roaring flames. Because developers are targeting wider colour spaces than sRGB, the oversaturation observed under SDR wasn’t present. Earthy browns and skin tones appeared mainly neutral, without an undesirable red push – though sometimes this went too far with a somewhat clay-like appearance to earth that should be slightly richer and redder. Some skin tones could also be affected, appearing slightly undersaturated in certain scenes. Vegetation showcased fairly deep and in places lush-looking greens with more muted and minty shades mixed in – again, without overdone yellowish greens or overly bright and eye-catching shades. Some golden and green shades appeared a touch muddy and slightly browner than we’d expect, though, lacking a certain liveliness. Bright oranges sometimes appeared a touch duller and browner than they should whilst darker oranges sometimes verged a bit too much on red – though less so than under SDR. These inaccuracies aren’t something everyone will notice when viewing the monitor in isolation as they aren’t extreme. We still felt the overall look was vibrant where intended, but with more appropriate saturation than when using the native gamut under SDR.
Interpolation and upscaling
The screen offers various scaling options in ‘Image’ – ‘Aspect Control’; ‘Full’, ‘Equivalent’, ‘1:1’ and ‘16:9 (25”W)’. ‘Full’ will use all pixels of the monitor with an interpolation process used – this is the only option that can be used with ‘Adaptive-Sync’. ‘Equivalent’ is sometimes referred to as ‘Aspect’ on other models and should use as many pixels as possible whilst respecting the aspect ratio of the source resolution to avoid stretching or distortion. Black space surrounds the image where appropriate. ‘1:1’ is a pixel mapping feature which only uses the pixels called for in the source resolution without scaling, filling in unused pixels as black space. This section of the OSD video demonstrates the feature. When running 1920 x 1080 (Full HD or 1080p) using the ‘Full’ setting, the interpolation process used provided a bit of a softer look than a native Full HD screen of this size. This was offset quite effectively by setting ‘Vivid Pixel’ (available with ‘GameVisual’ set to ‘User’ for example) to ‘60’ or perhaps ‘70’. Some elements appeared a bit over-sharpened but we didn’t feel it looked too bad – 27” Full HD doesn’t look particularly amazing at the best of times, even natively. With the monitor set to 3840 x 2160 (‘4K’ UHD), the downsampling mode worked much as we’ve seen on other models with the feature. It doesn’t appear like a native 27” UHD model (using the ‘27” W’ setting to match that size) as this monitor doesn’t benefit from the same tight pixel density. But it looks quite crisp, as if very strong anti-aliasing and a bump up in texture resolution has been applied to the game.
Video review
Timestamps:
Subpixels and Fringing
Image Retention and Burn-in
Features & Aesthetics
Contrast
Colour reproduction
HDR (High Dynamic Range)
Responsiveness (General)
Responsiveness (VRR)
Conclusion
Positives Negatives Vibrant output with very strong colour consistency, good DCI-P3 support and flexible sRGB emulation
Limited support for Adobe RGB and Rec. 2020, gamma averages ‘2.2’ but deviates at low and upper end providing some detail loss in places Exceptional static contrast performance, effective glare-handling from the screen surface and good bursts of brightness under HDR A bit of a grainy look and hazing from ambient lighting due to screen surface, brightness more limited than some LCD models and inability to show appropriate saturation at high brightness due to unfiltered white subpixel Exceptional pixel responsiveness without perceived overshoot at any refresh rate, good VRR support and exceptionally low input lag No BFI or pixel strobing option, some VRR flickering for dark to medium-dark shades during significant frame rate fluctuations, ‘HDMI 2.1 VRR’ support but HDMI 2.0 bandwidth Hefty and premium feel to stand, decent pixel density and ‘desktop real estate’ from resolution, very good ergonomics and feature-rich OSD Expensive for a QHD option, fringing (plus image retention and burn-in concerns) make it less than ideal for heavy productivity usage, ‘chunky’ and potentially divisive styling
