Gigabyte AORUS CV27F

Interlace pattern artifacts

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 bands of a slightly lighter and slightly darker version of the intended shade. We did not observe any dynamic ‘interlace pattern artifacts’, although we did observe some faint static interlace patterns in places. These were most noticeable on some orange and blue shades, plus some medium and lighter grey shades. These were not particularly obvious and most users shouldn’t find them bothersome – or necessarily notice them at all.

We also observed some flickering (pixel inversion) issues, possibly related to imperfections in the voltage control of the monitor. These could be observed when close to walls on some darker scenes in games. The release notes for the firmware update we had running at the time of review (F04) specifically mentioned that some backlight issues were fixed. It’s possible that some but not all instances of this sort of thing were looked at. It occurs if the brightness of the monitor is set above ‘5’ (>55 cd/m² or so) and didn’t seem to be affected by other things (including refresh rate, ‘FreeSync’ or ‘Overdrive’ setting). We’ve made Gigabyte aware of this and hopefully it can be addressed in a future firmware update, which will be provided for users to apply themselves via the OSD Sidekick software. The issue is highlighted in the section of video review below and as noted isn’t something we generally found bothersome in a well-lit room.

Responsiveness

Input lag

We used a small tool called SMTT 2.0 and a sensitive camera to compare the CV27F’s latency with a screen of known latency. To help maximise accuracy, over 30 repeat readings were taken. Using the method, we measured 4.35ms (a little under 3/4s of a frame @165Hz) of input lag. The status of the ‘FreeSync’ setting in the OSD made no measurable difference to this result and neither did setting the monitor to our preferred refresh rate (144Hz). This value is influenced both by the element of input lag you ‘feel’ (signal delay) and the element you ‘see’ (pixel responsiveness). It indicates a low signal delay which shouldn’t bother most users. We don’t have the means to accurately measure input lag with Adaptive-Sync active in a variable refresh rate environment or with HDR active in an HDR environment.

Perceived blur (pursuit photography)

Our article on responsiveness explores some of the key concepts surrounding monitor responsiveness. Chief amongst these is the concept of perceived blur, which is contributed to by both the pixel responsiveness of the monitor and the movement of your eyes as you track motion on the screen. This second factor is dominant on modern monitors, although slower than optimal pixel responses are still an important contributor. We also look at ‘pursuit photography’, an image capture technique which uses a moving camera to capture motion on a screen in a way that reflects both elements of perceived blur.

The images below are pursuit photographs taken using the UFO Motion Test for ghosting, where the UFO moves across the screen from left to right at a frame rate matching the refresh rate of the display. The test is set to run at its default speed of 960 pixels per second, which is a practical speed for such photographs and sufficient to help highlight key weaknesses. The monitor was tested at 60Hz (directly below), 100Hz, 144Hz and 165Hz with all of the ‘Overdrive’ settings tested; ‘Picture Quality’, ‘Balance’ and ‘Speed’. Although not documented here, 120Hz behaved some way between the tested refresh rates (100Hz and 144Hz), as you might expect. All rows of the UFO Motion Test were used, to show a range of pixel transitions between various shades. The final columns show some reference screens for comparison, where possible. The first is the LG 32GK850G, a relatively fast VA model using what we consider its optimal response time setting (plus G-SYNC active in the graphics driver, which speeds up its pixel responses). The second is the ViewSonic XG240R, a fast and well-tuned TN model (particularly at high refresh rates) that shows how things look where pixel responsiveness isn’t really a limiting factor.

At 60Hz, shown above, the UFO appears relatively softly focused without clear detail. This reflects significant perceived blur due to eye (camera) movement. You can see this sort of soft and unfocused look to the object itself on the reference shots as well. There are also various amounts of trailing behind the UFOs, caused by weaknesses in pixel responsiveness. The greatest weaknesses in pixel responsiveness are evident using the ‘Picture Quality’ setting. There’s a bold and heavy trailing behind the object, giving the UFO a distinct smeary appearance when it’s in motion. The ‘Balance’ setting cuts down on this somewhat, although some weaknesses still remain for the dark background (top row) and to a lesser extent medium background (middle row). The ‘Strong’ setting removes this conventional trailing, but there’s now some fairly strong overshoot (inverse ghosting) evident. Including some bright ‘halo’ trailing for the medium background and particularly the light background, plus some inky-looking overshoot for the dark background. The optimal setting here would depend on personal preferences for speed vs. overshoot, with either the ‘Balance’ or ‘Speed’ setting being used. The LG 32GK850G reference appeared some way between the ‘Balance’ and ‘Speed’ settings here and was better optimised overall at 60Hz. The following image shows how things look with the refresh rate bumped up to 100Hz.

At 100Hz, shown above, the UFO is quite a bit narrower with sharper focus. This reflects a significant reduction in perceived blur due to eye movement. Varying degrees of trailing can again be seen behind the object. This is strongest with the ‘Picture Quality’ setting. The ‘Balance’ setting cuts it down a bit, but there’s still significant bold trailing behind the UFOs, especially for the dark and medium background – it gives the UFO a rather smeary appearance during motion. The ‘Speed’ setting cuts this down significantly, so a little remains for the dark and medium backgrounds. It’s replaced with a little overshoot in places, including some ‘shadow trailing’ for the dark background. The light background shows some reasonably strong overshoot in the form of ‘halo’ trailing. We’d consider the ‘Speed’ setting optimal here. The reference screen, unsurprisingly as it’s a well-tuned high refresh rate TN model, gives a ‘cleaner’ performance here with very little overshoot or conventional trailing to speak of. The image below shows what things look like with a further bump up in refresh rate to 144Hz.

At 144Hz, above, the UFO appears slightly narrower and more sharply focused. This indicates a further decrease in perceived blur due to eye movement. The overall pixel response behaviour is fairly similar to 100Hz, although the trailing from the weaker than optimal pixel transitions extends further backwards and appears bolder in places. This is due to the increased pixel response requirements of the higher refresh rate. The ‘Balance’ setting is now clearly sub-optimal in terms of pixel response performance, with significant trailing for the dark and medium background and even some ‘powdery’ trailing for the light background. The ‘Speed’ setting removes a lot of this, although some weaknesses remain. The light background shows bright ‘halo’ trailing, although this is subdued compared to lower refresh rates. We again consider the ‘Speed’ setting optimal here. Both reference shots show improved performance, though, with less conventional trailing and lower overshoot. As far as high refresh rate VA models go there are certainly much slower examples out there than what’s seen with the Gigabyte, though! Below you can see how things appear with a slight bump up in refresh rate to 165Hz.

At 165Hz, above, the UFO appears with slightly clearer internal detailing. This indicates a slight decrease in perceived blur due to eye movement – nothing major, it’s only an additional 21Hz. The overall pixel response behaviour is very similar to 144Hz in this test. We again prefer the ‘Speed’ setting here. The ‘Balance’ setting is simply not effective enough, giving a lot of ‘heavy powdery’ and ‘smeary’ trailing and not really putting the high refresh rate to good use. This isn’t a clear-cut choice for everyone, though, due to the additional overshoot using the ‘Speed’ setting. We feel a setting some way between these two might be preferable, but of the available options we’d take the faster of the two. Although not clear in this particular test, we observed some overdrive artifacts at 165Hz which were not evident to the same extent at lower refresh rates such as 144Hz. We describe these using in-game testing shortly, but they were sufficient for us to prefer setting the monitor to 144Hz rather than 165Hz.

As well as increasing refresh rate to minimise perceived blur due to eye movement, the monitor offers an alternative with its ‘Aim Stabilizer’ feature. This is a strobe backlight setting that causes the backlight to pulse at a frequency matching the refresh rate of the display – either 100Hz, 120Hz, 144Hz or 165Hz. By its very nature, this mode causes the backlight to flicker at a rate matching the refresh rate of the display – individual sensitivity to this flickering varies. Some users may notice accelerated eye fatigue when using this setting even if they aren’t actively noticing any flickering. The pursuit photographs below were taken with the monitor set to 100Hz using its ‘Aim Stabilizer’ feature. A few reference screens are also shown for comparison, using their respective strobe backlight settings at 100Hz. The AOC C24G1 using MBR (Motion Blur Reduction) and the Dell S2417DG using ULMB (‘Ultra Low Motion Blur’).

With ‘Aim Stabilizer’, you can see that the object itself appears significantly sharper with clearer internal detailing. This reflects a significant decrease in perceived blur due to eye movement, which is the main aim of a strobe backlight setting such as this. However; you can also see significant overshoot behind the object. The overshoot is split into fragments due to the strobing nature of the backlight. This overshoot is stronger with a greater number of fragments compared to the reference shots. The pursuit photographs below were taken with the monitor set to 165Hz. Note that refresh rates between 100Hz and 165Hz were tested but are not documented here – they were some way between the two in terms of the trailing behaviour, generally closer in appearance to 165Hz (below) compared to 100Hz (above).

The object itself now appears with excellent sharp internal detailing, with the notches on each UFO segments distinctly visible. There is again some overshoot behind the UFOs, somewhat lower than at 100Hz. That’s in part because it’s somewhat masked by bold repetitions of the object itself, particularly for the medium background. These repetitions are due primarily to the pixel responses not keeping up with the rigorous demands of the refresh cycle. The all-encompassing term ‘strobe crosstalk’ is used to describe this fragmented trailing around the object (behind in these examples – but it can also be in front). Because not all areas of the screen refresh simultaneously, the appearance of strobe crosstalk can differ depending on how high up or low down on the screen the movement is being observed. This was also evident at 100Hz (and other refresh rates not documented), but displaced slightly so it didn’t coincide with any of the pursuit photos taken for this test. The image below shows pursuit photographs running from the top to bottom regions of the screen, with the monitor set to 165Hz and using ‘Aim Stabilizer’.

You can see quite a bit of strobe crosstalk, varying in its appearance at different points of the screen. Further up the screen there is some quite bold strobe crosstalk in front of the UFOs. Further down and towards the central region it appears behind the UFO, whilst towards the bottom you can see strong strobe crosstalk both in front and behind the UFO. We certainly didn’t find the overall strobe backlight performance to be very ‘clean’ on this model, as we explore with subjective in-game testing shortly. Whilst the strobe crosstalk was somewhat reduced at lower refresh rates, particularly 100Hz, it was still noticeable in places and the increasingly obvious overshoot was quite distracting to us as well. This all had implications for the overall motion clarity of the image.

Responsiveness in games and movies

On Battlefield V, where the frame rate kept up with the 165Hz refresh rate, the monitor provided strong fluidity. 2.75 times as much visual information is being provided every second as a 60Hz monitor or this monitor running at 60Hz. This provides an excellent ‘connected feel’, which describes the precision and fluidity you feel when interacting with your character on the game and the game world. The low input lag helps in this respect as well, although this isn’t a feeling that low input lag alone can replicate. In addition, the perceived blur due to eye movement is significantly reduced – much as demonstrated earlier using Test UFO. The step up from 144Hz to 165Hz is not dramatic, though. There is a slight increase in ‘connected feel’ and a slight decrease in overall perceived blur, but there was that issue with patterned overshoot artifacts that we raised earlier. Specifically, you could see overshoot with a clear interlaced pattern of alternating darker and lighter components in places, giving a jagged appearance to some of the overshoot. This was most pronounced if the monitor is set to 165Hz, even if the frame rate dips with Adaptive-Sync active and hence the refresh rate also dips. With the monitor set to 144Hz or 120Hz it is still there to a degree, but is much more tolerable and less ‘in your face’. We therefore much preferred keeping the monitor at 144Hz to avoid this issue.

Most of the pixel transitions were performed rapidly for a VA panel, using our preferred ‘Speed’ setting. Especially where medium and lighter shades were dominant (daylight maps, which are common on BFV), the monitor certainly didn’t give an ‘uncompetitive’ feeling and looked and felt rather snappy overall. There was a bit of ‘light powdery’ trailing in places for some of these transitions, but this was minor and not very widespread. There were some more pronounced weaknesses to be aware of for some other pixel transitions, however. Some were performed noticeably slower than optimal, particularly where dark shades dominated. Strafing past a tree trunk at twilight or under heavy fog, for example, produced a ‘heavy’ powdery trailing. For some transitions this had a somewhat ‘smeary’ quality to it and there was what we call ‘break-up trailing’. Whereby some constituent shades contained in the object or background appear to ‘leach out’ in a slightly colourful way. Like wetting a page with some dark coloured water-soluble ink on it, with some reddish or purple hues separating out from the ink. This was quite well-contained on this model overall and there weren’t really any instances of ‘extended smeary’ trailing with a smoke-like appearance.

There were some more noticeable examples of overshoot where many darker shades were displayed as well. Moderately strong ‘halo’ trails in places which stood out due to being significantly brighter than the object or background colour. As well as some ‘dirty’ trailing that was darker than the object or background colour. This wasn’t what we’d call ‘extreme’ overshoot and not everybody would find it bothersome – but users who are sensitive to it certainly might. We’d certainly say this was one of the faster high refresh rate VA models we’ve tested, although not necessarily the fastest or the one with the ‘cleanest’ (lowest overshoot) transitions. We’d say it’s most similar to the AOC C24G1 using its ‘Strong’ overdrive setting, although not quite as well-balanced due to having both some more noticeable overshoot and some more noticeable slower than optimal pixel transitions (causing the ‘break-up trailing’). That’s a model that we’ve gathered a lot of user feedback on, including from competitive gamers – and for such uses the ‘Strong’ overdrive setting on that one generally goes down well. The section of the video review below highlights some of the strengths and weaknesses in the monitor’s pixel overdrive performance, again using BFV as an example.

We don’t have much to add to the fairly extensive analysis above using Shadow of the Tomb Raider as an example. Although this title frequently showcased darker shades due to it having many dark or heavily shaded locations. These, naturally, brought out some of the slower than optimal pixel transitions and the instances of more noticeable overshoot. We didn’t actually find this detracted too much from the gameplay on the whole and found that, even though the performance wasn’t a ‘clean’ as it could’ve been, there weren’t the sort of extensive weaknesses found on some high refresh rate VA models. We didn’t get the kind of dizzying sensation or clear increases in overall perceived blur that some models provide. We also tested a range of video content, including 24-30fps videos on Netflix and suchlike and 60fps YouTube videos. For the lower frame rate content there was slight overshoot in places, but nothing obvious. The frame rate itself was definitely the key limiting factor here and things really didn’t look markedly different to how they would on a technically much faster and overshoot-free monitor. For the 60fps content there was some slightly more noticeable overshoot in places, but with the monitor running at 144Hz (or 120Hz, if you prefer, due to the even division of 60fps) this was fairly tame overall. Sensitivity to overshoot varies, so if you find it too much you might consider using the ‘Balance’ setting instead. But you’d then need to contend with some slower than optimal pixel transitions, even for 60fps content – refer to the pursuit photographs earlier. Even with the overshoot, we preferred sticking to the ‘Speed’ setting when the monitor was set to relatively high refresh rates.

FreeSync – the technology and activating it

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. There is a list of GPUs which support the technology here, with the expectation that future AMD GPUs will support the feature too. 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 CV27F supports FreeSync via DP and HDMI on compatible GPUs and systems. More specifically, ‘FreeSync 2’ is supported by the monitor, encompassing HDR support (this feature is not AMD-specific) and a relatively generous effective range of operation. Note that HDR can be activated (at the same time as FreeSync) via DP 1.2+ or HDMI 2.0. If fully installed, AMD drivers feature Radeon Settings, which makes activation of the technology very simple and something that usually occurs automatically. First make sure that you have ‘FreeSync’ set to ‘ON’ in the ’Gaming’ section of the OSD. You should then make sure the GPU driver is setup correctly to use FreeSync, so open ‘AMD Radeon Settings’ and click on ‘Display’. You should then ensure that the first slider, ‘AMD FreeSync’, is set to ‘On’. If you hover over this, it will also report the variable refresh rate display supported by the display.



The Gigabyte AORUS supports a variable refresh rate range of 48 – 165Hz. That means that if the game is running between 48fps and 165fps, the monitor will adjust its refresh rate to match. When the frame rate rises above 165fps, the monitor will stay at 165Hz 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 165fps, 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 >165fps). 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 48Hz (48fps) floor of operation for FreeSync. If a game ran at 35fps, for example, the refresh rate would be 70Hz to help keep tearing and stuttering at bay. This feature is used regardless of VSync setting, so it’s only above the ceiling of operation where the VSync setting makes a difference.

VSync is configured in the ‘Gaming’ section of ‘Radeon Settings’, where it is referred to as ‘Wait for Vertical Refresh’. You can either configure this globally under ‘Global Settings’ or for each game individually. 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. The final option, ‘Enhanced Sync’, is a relatively new addition to the driver. 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 than a monitor feature.



Some users prefer to leave VSync enabled but use a frame rate limiter set a few frames below the maximum supported (e.g. 162fps) 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 enable ‘Refresh Rate’ under ‘AORUS Info’ in the ‘GameAssist’ section of the OSD, this will display the refresh rate of the display and therefore indicate the frame rate if ‘FreeSync’ is active and the frame rate is within the variable refresh rate range of the display. 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

We used this monitor whilst playing a range of game titles, with FreeSync active. As usual we found the experience homogeneous across the different game titles and indeed any issues identified with FreeSync in one title but not another would indicate an issue with the game or GPU driver rather than the monitor. We’ll therefore just focus on one title for this section; Battlefield V. With the flexibility offered in the graphics options, it was possible to test a large range of frame rates and therefore the full range of refresh rates supported on this model. The Radeon RX 580 used in our test system was able to maintain a fairly solid 165fps (or 144fps using our preferred 144Hz setting) with graphics settings reduced quite far. There were still dips a bit below this where action intensified. These slight dips were far more palatable with FreeSync enabled, as without it they’d result it obvious tearing (VSync off) or obvious stuttering (VSync on). This stuttering is obvious to us, at least – but sensitivity to this sort of thing varies.

With further increases to graphics settings and frame rate hovering closer to 100fps, FreeSync still did its thing to get rid of tearing and stuttering from frame rate and refresh rate mismatches. A very nice bonus in our view. There was an increase in perceived blur and decrease in connected feel from the drop in frame rate – that is not something FreeSync can address and it’s still beneficial to have a higher frame rate where possible. Also noticeable was an increase in overshoot intensity using our preferred ‘Speed’ setting for ‘Overdrive’. At 100fps or so this increase was noticeable to us and there were some stand-out examples of bright and colourful ‘halo’ trailing and dark ‘dirty’ trailing that were quite a bit more obvious than at much higher frame rates. As frame rate dropped further, the overshoot intensified further. It wasn’t as extreme as we’ve seen on some models but was still clearly noticeable to us (sensitivity varies). The alternative would be to use the ‘Balance’ overdrive setting, but there are then some widespread weaknesses in pixel responsiveness – even when your frame rate and refresh rate is well into the double digits and 100fps is a distant memory.

The reason for this increase in overshoot, which is common on FreeSync models, is that the pixel overdrive is tuned with the maximum refresh rate of the monitor in mind. As refresh rate drops, either because you’ve selected a lower static refresh rate or because your frame rate drops and you’ve got FreeSync active, the pixel overdrive should really be re-tuned. The voltage tuning in the overdrive circuit for 144Hz is very different to much lower refresh rates. This is something G-SYNC models (with the module) handle better as they employ ‘variable overdrive’, which slackens off the aggressiveness of the pixel overdrive appropriately as refresh rate reduces. For frame rate dips below 48fps, the monitor will stick to a multiple of the frame rate with its refresh rate – something AMD calls LFC (Low Framerate Compensation). This worked effectively to reduce tearing and stuttering. There was a brief stuttering when this activated, but nothing extreme and not something users should worry about unless they’re frequently going above or below the LFC boundary. A final point we’d like to make is that we observed slight momentary flickering following large fluctuations (generally large drops) in frame rate, regardless of whether LFC is being used or not. This is widely observed on VA models and certainly not unique to this one.

Nvidia Adaptive-Sync (‘G-SYNC Compatible’)

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 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’. Some models are specifically validated as G-SYNC compatible, which means they have been specifically tested by Nvidia and pass specific quality checks. With the CV27F, you need to connect the monitor up via DisplayPort and enable ‘FreeSync’ in the ‘Gaming’ section of the OSD. 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. Press OK, then turn the monitor off then on again so that it re-establishes connection – the technology should now be active.



You will also see in the image above that it states: “Selected Display in not validated as G-SYNC Compatible.” This means Nvidia hasn’t specifically tested and validated the display, not that it doesn’t work. This model worked properly using Adaptive-Sync (G-SYNC compatible mode) on our Nvidia GTX 1080 Ti, offering an experience that was very similar to using AMD FreeSync. This included support for HDR whilst Adaptive-Sync was active. A slight difference is that the floor of operation appeared to be 65Hz (65fps) rather than 48Hz (48fps). However; an LFC-like technology was supported, with the monitor keeping at a multiple of the frame rate with its refresh rate. If anything this was preferable to having the refresh rate dip below 65Hz due to the even more extreme overshoot that would introduce. Although, even at 65Hz or anything near it, we’d still describe the overshoot as strong in places using the ‘Speed’ setting of the OSD. As noted in the FreeSync section, pixel overdrive tuning for a broad range of refresh rates is certainly something that Nvidia G-SYNC models (with a module) handle better than this one.

Our suggestions regarding use of VSync also apply, but obviously you’re using Nvidia Control Panel rather than Radeon Settings 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’).



Finally, note again that you can activate ‘Refresh Rate’ under ‘AORUS Info’ in the ‘GameAssist’ section of the OSD to see if the technology is working. This will rapidly adjust as frame rate fluctuates, whereas if Adaptive-Sync isn’t being used it will stay at the static refresh rate you’ve selected.

Aim Stabilizer

Earlier in the review, we introduced the ‘Aim Stabilizer’ feature, its principles of operation and how it performs using specific tests. When using ‘Aim Stabilizer’ or any strobe backlight feature, it’s essential that your frame rate exactly lines up with the refresh rate of the display. If that isn’t the case, you’re left with extremely obvious stuttering or juddering, which stands out because there’s very little perceived blur due to eye movement to mask it. For some transitions there’s a significant amount of bright ‘halo’ overshoot trailing, with clear jagged interlacing patterns. We tested a range of game titles using the setting and also tested it at a range of refresh rates, but here we’ll focus on Battlefield V at a solid 165fps and the monitor set to 165Hz. As noted earlier, lower refresh rates (with matching frame rates) didn’t really improve things and you had even more obvious overshoot to contend with. Coupled with strobe crosstalk, a repetition of some objects behind or in front of them, the overshoot was detrimental to overall motion clarity. We also observed some fairly obvious flashes and green and magenta when observing lighter shades, especially slender bright object. It’s not uncommon to see this to a degree with strobe backlight implementations, especially on models with generous colour gamuts. But we found it quite noticeable on this model.

In addition to these issues, the backlight flickering (matching the refresh rate of the display) could bother sensitive users. We preferred the normal flicker-free operation of the backlight in general and found that less fatiguing visually, although sensitivity to flickering varies. If a user can manage to look past these issues, plus is fine with the locked brightness at a moderate value, there is some advantage to be had in terms of reduction in perceived blur from the strobe backlight setting. Objects remain more detailed and more sharply focussed, giving a nice competitive edge which some users might find appealing. Whilst this mode certainly has utility, we didn’t find this to be a particularly ‘clean’ or flexible strobe backlight implementation and found it visually uncomfortable in many respects.

HDR (High Dynamic Range)

The ideal HDR monitor is able to distinctly output very deep dark shades and very bright light shades on the screen at the same time. It’s also able to display an excellent range of shades between these extremes, with a nuanced variety of dark, medium and light shades. A key to such output is precise control of the illumination, something OLED or other backlightless technologies excel at. For LCDs, a complex backlighting solution with many dimming zones is useful. Hundreds or more dimming zones in the form of an FALD (Full Array Local Dimming) solution, for example. Precise control of illumination enables the monitor to display intricate mixtures of light and dark content. Some sections of the screen can be brightly illuminated, giving good ‘pop’ to bright shades, whilst other sections of the screen can be very dimly lit to maintain good depth and atmosphere for dark shades. HDR is about more than just contrast, though – the output of a large range of colours is also important. The ultimate goal is coverage of a massive colour gamut known as Rec. 2020, whilst a more achievable near-term aim is for a monitor to cover at least 90% DCI-P3 (a Digital Cinema Initiatives standard colour space). Finally, HDR makes use of 10-bit+ precision per channel, so it’s desirable for the monitor to support (at least) 10-bits per subpixel.

It is specifically the HDR10 pipeline which is currently used on monitors at the moment and the common standard supported most widely in games and other applications. For most games and other full screen applications that support HDR, the Gigabyte AORUS CV27F automatically switches into its HDR operating mode. You’ll know HDR is active on the monitor as if you go into the OSD and navigate to a section other than ‘Gaming’ you will see ‘HDR ON’ listed towards the top left. On newer versions of Windows 10, relevant HDR settings in Windows are found in ‘Windows HD Color settings’ which can be accessed via ‘Display settings’ (right click the desktop). Most game titles will activate HDR correctly when the appropriate in-game setting is selected. Occasionally you may find HDR activates or deactivates incorrectly in a game the first time it switches – the image will look clearly wrong and blown out if this happens. Simply ‘alt-tabbing’ out and back into the application or switching the HDR off/on again in the game will solve this. A minority of game titles that support HDR will only run in HDR if the setting is active in Windows as well. Specifically, the toggle which says ‘Play HDR games and apps’. If you want to view HDR movies on a compatible web browser, for example, you’d also need to activate the ‘Stream HDR Video’ setting. These settings are shown below. Also note that there’s a slider that allows you to adjust the overall balance of SDR content if HDR is active in Windows. This simply simply acts as a digital brightness slider, so you lose but never gain contrast by adjusting it. Regardless of what this was set to, the image appeared to lack some depth and contrast and was noticeably over-sharp. So we’d recommend only activating HDR in Windows if you’re about to specifically use an HDR application that requires it, and have it deactivated when viewing normal SDR content on the monitor.

Although our testing is focused on HDR PC gaming, our observations also apply to HDR movie content and running HDR on a compatible games console. The experience is dictated and, in many respects limited, by the capabilities of the screen itself. We tested a range of titles under HDR, but will simply be focusing on two titles in this section that we know offer good HDR performance on screens with a good HDR implementation; Battlefield V and Shadow of the Tomb Raider. Under HDR, the settings that would usually appear in the ‘Picture Mode’ menu (including brightness, sharpness and colour channel adjustments) are locked off. This is quite usual for an HDR monitor as such things are (supposed to be) carefully controlled to a required standard with close coordination between the content, the GPU and the monitor. This was different to the AD27QD we tested, where users were given far too much flexibility to change settings. Also unlike the AD27QD, the HDR experience was quite similar on the AMD and Nvidia GPU we tested.

The Gigabyte AORUS CV27F is VESA DisplayHDR 400 certified. This is the lowest HDR level which VESA will certify for. It means that only a very basic HDR experience is provided, with some but certainly not all desirable HDR boxes ticked. One area where the AORUS achieves and actually exceeds the VESA DisplayHDR 400 requirements is colour gamut, with 90% DCI-P3 specified by the manufacturer. We were able to confirm 90% DCI-P3 coverage using our colorimeter, as shown in the gamut representation below. The red triangle shows the monitor’s colour gamut, whilst the blue triangle is the DCI-P3 and green triangle sRGB colour spaces. On this point alone, the monitor is technically at the level required for VESA DisplayHDR 1000 certification – but there are of course other boxes that have to be ticked for that as well. Because DCI-P3 is the near-term standard game developers and HDR movie directors have in mind when creating HDR content, it makes sense to have good coverage of this colour space for HDR purposes.

Colour gamut 'Test Settings'

When running in HDR, a sharpening filter is applied, which is moderate but not extreme on this model. We’d prefer if this could be adjusted or removed and find it more noticeable than this sort of filtering applied to models with significantly higher pixel density. Although we still didn’t find it as annoying as we sometimes do with such things. The colour gamut was put to good use under HDR. We observed some oversaturation earlier in the review under SDR (content targeting the sRGB colour space), for example certain greens appearing with too strong a yellow hue and woody tones appearing a bit too red. This is curtailed under HDR as the DCI-P3 colour space is targeted, with environments on both titles appearing rich and natural. There was plenty of vibrancy where it was warranted, for example brightly painted pottery, striking purple flowers and roaring orange flames. Some colourful licks of paint, such as bright blue boats and pea green painted farm machinery were also nice and vivid. These shades sit beyond the boundaries of the sRGB colour space, so the stronger saturation is applied appropriately rather than universally under HDR.

The monitor supports 10-bit colour via 8-bit + FRC. The enhanced precision used under HDR provided a nuanced variety of dark shades, giving shaded regions a more believable look. This was very different to simply raising the gamma and lightening many of the shades and it maintained a natural rather than ‘flooded’ look to the image. The enhanced precision also applied to brighter shades. Fine gradients such as the sun’s rays in the sky, mist and smoke effects appeared smoother and again showed a greater nuanced variety of shades and a more natural progression. The image below is one of our favourites from Shadow of the Tomb Raider for showcasing HDR on a monitor. The photo is purely for illustrative purposes and in no way represents how the monitor appeared running HDR first hand.



This scene looked rather bright overall, with the moderate luminance levels supported being put to work. However; a significant drawback of the basic VESA DisplayHDR 400 certification is that it does not mandate any sort of local dimming. This model’s backlight is controlled as one unit, which as noted in the contrast section means there is no contrast advantage to using HDR. An effective local dimming solution is a key ingredient for a ‘proper HDR experience’, without question. For this scene, a ‘proper HDR experience’ would involve the bright elements such as the sun beaming down, the glint of the sun off the water and waxy leaves appearing brilliantly bright. And there would be a nice mixture of less bright (but still bright) regions surrounding that. The shaded areas of vegetation, for example in the left of the image but mixed in elsewhere as well would appear relatively deep. On this model the dark areas didn’t have the required depth and the bright elements didn’t have the eye-catching brightness that HDR should deliver. The overall scene was just rather bright – some would find this uncomfortable and it certainly accelerates eye fatigue. The strong native contrast of the monitor helped to a degree and prevented such elements looking completely flooded, although there were definite limitations at both the high and low end with the simple backlight solution used. Where the content was predominantly dark, we also felt the backlight lit up too strongly and such scenes would appear more appropriate and atmospheric with a lower luminance level – so even with a single backlight unit being used, finer control would have helped. The section of the video review below focuses on the HDR performance of the monitor and runs through various examples on both test titles.

Interpolation and upscaling

Some users might want to use a lower resolution than the native 2560 x 1440 (WQHD) of the display. Either for extra performance or because they’re using a device such as a games console that doesn’t support the resolution. The monitor provides scaling functionality via both DP and HDMI. It can be run at resolutions such as 1920 x 1080 (Full HD) at up to 60Hz and can use an interpolation (scaling) process to fill the pixels of the screen up. The monitor also supports internal upscaling to 3840 x 2160 (‘4K UHD’) at up to 60Hz, which is useful for devices such as games consoles that support UHD but not WQHD output. 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.

The monitor offers various ‘Display Mode’ settings in the ‘Gaming’ section of the OSD, as explored in the OSD video. This includes, amongst others, a ‘1:1’ pixel mapping feature that will display only the pixels called for in the source resolution with a black border for the remainder. And the default option, ‘Full’, which will use interpolation and map the source resolution onto the 2560 x 1440 pixels of the display. Considering the Full HD (1920 x 1080) resolution, the monitor’s interpolation process is one of the better ones we’ve come across. There was a fair degree of softening compared to viewing a native 1920 x 1080 (Full HD) screen with decent sharpness. This could be partly offset by using the ‘Sharpness’ setting in the OSD or alternatively ‘Super Resolution’ (found in the ‘Gaming’ section). We actually quite liked the look that setting ‘Super Resolution’ to ‘1’ gave the image when running in interpolated Full HD. It didn’t look as crisp and detailed as a native Full HD display, but was surprisingly good in that respect and better than we’ve seen on most monitors. Users should experiment with different settings according to their own preferences, however.

As usual, if you’re running the monitor at 2560 x 1440 and viewing 1920 x 1080 content (for example a video over the internet or a Blu-ray, using movie software) 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 curve

This monitor adopts a 1500R curve. This is a bit steeper than the curvature on most 27” curved models, which is usually 1800R or possibly even gentler. The curve is something that often appears quite exaggerated in photos and videos of the monitor, with an odd optical pincushion effect. When you’re sitting in front of the monitor using it normally, this ‘pincushion’ effect isn’t observed. The curve is something we found to be quite a subtle and natural addition, one which we adapted to quite quickly and that drew us into the experience a bit. It gives a slight extra feeling of depth and some would argue it’s beneficial for viewing comfort as well. We can attest that we found the monitor comfortable to use, although we don’t find most modern flat monitors uncomfortable. In fact, once we’d become used to the 1500R curve of this model, going back to flat models was an odd experience as they initially appeared convex (bending away at the edges) even though they weren’t. Your eyes and brain adjust to this after several hours, just as you get used to curved models. We’d therefore consider the curve something that most users will adapt to and actually quite enjoy using. Designers or users who simply prefer geometric perfection may indeed prefer flat screens, but for most users it’s certainly not something to be afraid of. The images below are just for illustrative purposes and greatly exaggerate the effect of the curve, as noted earlier.

Video review

The video below summarises some of the key points raised in this written review and shows the monitor in action. The video review is designed to complement the written piece and is not nearly as comprehensive.

Timestamps:
Features & Aesthetics
Contrast
Colour reproduction
HDR (High Dynamic Range)
Responsiveness

Conclusion

Although there’s been a push towards screens with higher resolutions and pixel densities, some users find the 1920 x 1080 (Full HD) resolution suitable for their needs. By using a VA panel with this resolution and combining it with a host of attractive features (including a 165Hz refresh rate), the Gigabyte AORUS CV27F is one of the more interesting Full HD models launched recently. The 27” Full HD screen certainly doesn’t deliver breathtaking detail and clarity, as the pixel density is relatively low – but it makes it easier to push high frame rates to make the most out of the high refresh rates supported. The 1500R curve of the screen is something we got used to quite quickly and felt the screen was perfectly natural to use. The curve just drew us into the experience a bit, without making things feel weird. The monitor has sharp lines and a good solid powder-coated metal stand base, giving it a fairly solid look and feel overall. The comprehensive OSD and well-implemented ‘OSD Sidekick’ software (including user-upgradeable firmware feature) was also a nice touch. For users who like a touch of colour, there were some customisable RGB LED ‘wings’ at the rear – but the light from this was only really easily viewed from behind the monitor. So not particularly useful with the monitor up against a wall.

Contrast was the main strength of the monitor, as with any VA panel. Static contrast was relatively strong, giving a good atmosphere to dark scenes. There was a bit of ‘black crush’ and ‘VA glow’, although both were at a relatively low level so we didn’t feel the really soured the experience too much. The use of a light matte anti-glare screen surface with relatively smooth finish was also commendable, keeping the image free from any real graininess even when viewing the lightest content. Out of the box gamma tracking was also good, with plenty of flexibility related to that in the OSD as well. After a few tweaks elsewhere, the image was nicely balanced and quite vibrant and varied overall. There were some colour consistency weaknesses (losses of saturation towards the bottom and lesser extent sides of the screen), but these were minor for the panel type. Particularly from a reasonable viewing distance, sitting centrally. The generous but not extreme colour gamut (90% DCI-P3) helped inject some extra vibrancy into the image without intense oversaturation. It was also a suitable base for HDR, with the monitor supporting VESA DisplayHDR 400. As far as HDR experiences at this ‘level’ go, the monitor provided a well-balanced one overall. The nuanced shade variety was good and the colour gamut was used appropriately. On the contrast side, though, there was no advantage whatsoever to running the monitor in HDR over SDR. No local dimming was supported and the top end luminance wasn’t particularly high by HDR standards. Good enough for VESA HDR 400 certification – far from a ‘full fat’ HDR experience. Unlike on the AD27QD, the HDR experience was largely the same on our AMD and Nvidia GPUs. So that was good to see.

Responsiveness was something of a mixed bag, as is often the case with VA models. Input lag was nice and low and the monitor provided 165Hz output, which gave a pleasing ‘connected feel’ and a reduction in perceived blur at suitably high frame rates. We actually preferred keeping the monitor at 144Hz, though, as we noticed some particularly obnoxious overshoot artifacts at 165Hz. Overshoot was still a prominent feature at 144Hz, something that could be tackled by using the ‘Normal’ setting – which instead made instances of ‘powdery’ and ‘smeary’ trailing far more common. Whilst this persisted in places using the ‘Speed’ setting, it was not as widespread or obvious in general. For a VA model, the pixel responses were quite snappy overall and put the higher refresh rates to quite good use. But we felt a setting between ‘Normal’ and ‘Speed’ would’ve been an attractive addition. This was especially the case at reduced frame rates, with Adaptive-Sync active (and hence reduced refresh rates), where overshoot became rather strong using the ‘Speed’ setting. But obvious weaknesses under the ‘Normal’ setting persisted. Adaptive-Sync did its thing to get rid of tearing and stuttering, though, both via AMD FreeSync and Nvidia’s ‘G-SYNC Compatible Mode’.

An alternative was provided in the form of the ‘Aim Stabilizer’ strobe backlight setting, but we found this too ‘messy’ in terms of overshoot, strobe crosstalk and various other issues to be a setting we’d recommend. Overall the monitor is one of the more feature-rich Full HD models available and it puts most of its features to good use. The pricing reflects this broad feature-set. It provides strong contrast and fairly vibrant colour output, with respectable consistency for the panel type. It also provides a decent high refresh rate experience, with fairly snappy pixel responses overall and low input lag. Although there were imperfections there which could sour the experience for some.

The bottom line; a fairly vibrant and varied image with strong contrast and decent overall responsiveness for the panel type – but some imperfections in the pixel responses that could turn some users off.

 

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