ViewSonic XG240R

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 or 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 static interlace patterns, but we did observe dynamic interlace patterns on this model. Whilst observing movement on the screen, particularly at a slow to moderate pace, we could see the image appear to break up into a faint mesh pattern. The mesh patterns were quite faint and aren’t something everyone would notice or be bothered by and are typical for the panel used in this monitor. There were also occasional ‘waves’ of horizontal lines, more readily observed if viewing distance was also changed (i.e. head movement is included). The are something we’ve observed on some other models using this panel, but they don’t affect all units of a given model. Both types of pattern occurred independent of Adaptive-Sync being active or not and regardless of refresh rate. The image below was taken from the XG2402, which exhibited the same mesh-like dynamic interlace pattern. This image is from the UFO Motion Test ‘Moving Photo’ test page and shows the pattern towards the top left region in particular. Note again it is a very fine pattern in reality and not everyone will notice it.

Responsiveness

Input lag

A sensitive camera and a utility called SMTT 2.0 was used to assess the input lag of the XG240R. It was compared with a screen of known latency, with over 30 repeat readings taken to help maximise accuracy. Using this method we calculated 2.86ms (under ½ a frame at 144Hz) of input lag. This value reflects both the element of input lag you ‘see’ (pixel responsiveness) and the element you ‘feel’ (signal delay). It indicates a very low signal delay, which even sensitive users shouldn’t find bothersome. Note that we have no way to accurately measure input lag when Adaptive-Sync is doing its thing.

Perceived blur (pursuit photography)

Our responsiveness article explores the factors which affect responsiveness of a monitor. Chief amongst these is the concept of ‘perceived blur’, which is contributed to not only by the pixel responsiveness of the monitor but also eye movement as you track motion on the screen. It’s actually this eye movement that is generally the dominant contributor to perceived blur. A technique called pursuit photography is also introduced in the article, which uses a moving rather than stationary camera to capture motion on a monitor. This allows not just the pixel response behaviour to be reflected, but also reflects perceived blur due to eye (camera) movement. It’s therefore a much more accurate reflection of how motion appears to the eye when observing the screen in person.

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 for taking such photographs at and demonstrates both elements of perceived blur nicely. The UFOs move across the screen from left to right at a frame rate matching the refresh rate of the display. The monitor was tested at 60Hz (directly below), 100Hz and 144Hz with all ‘Response Time OD’ settings tested; ‘Standard’, ‘Fast’, ‘Faster’, ‘Ultra Fast’ and ‘Fastest’. All rows of the UFO Motion Test were used, with backgrounds of varying shade brightness (grey level) showcasing a range of pixel transitions. The final column shows at least one reference screen (Dell S2417DG) and where possible a second reference (ViewSonic XG2402), both set to their optimal response time setting. This gives an indication of how things should look in this test where pixel responsiveness isn’t really a limiting factor. Using this model’s predecessor is also serves as an interesting point of comparison.

At 60Hz, above, you can see that the UFO appears soft and unfocused. This indicates a moderately high level of perceived blur due to eye movement. The same observation can be made for the reference shots. In addition to this, there are various degrees and types of trailing behind the UFO which is caused by weaknesses in pixel responsiveness. For the ‘Standard’ setting the pixel overdrive is too weak, so you get a heavy ‘powdery’ trail behind which is quite bold and extensive. The ‘Fast’ setting cuts this down significantly, particularly for the dark background (top row) and light background (bottom row). The ‘Faster’ setting slightly cuts down on this further but introduces a bit of overshoot (inverse ghosting), which manifests as a slightly ‘shadowy’ appearance to the trailing in places. The ‘Ultra Fast’ setting increases this overshoot, giving a more obvious but not really extreme ‘shadowy’ appearance. The ‘Fastest’ setting completely overdoes things, introducing bright, colourful and very eye-catching overshoot. At 60Hz we’d consider ‘Fast’ or ‘Faster’ to be the optimal setting, most users will find either fine. Even with the ‘Fast’ setting there is some overshoot (‘shadowy’ trailing) for some transitions which aren’t highlighted in this particular test, however. The ‘Faster’ setting makes these more obvious and rather eye-catching. The following image shows how things look with a bump up in refresh rate to 100Hz.

At 100Hz, above, you can see that the UFO appears more tightly focused. This indicates a significant reduction in perceived blur due to eye movement. There is again various degrees of trailing behind the object. The ‘Standard’ setting is too lax with its pixel overdrive, giving a heavy ‘powdery’ trail behind the object. The ‘Fast’ setting, on the other hand, as good as eliminates this for all transitions. There is a very slight amount of overshoot (‘shadowy’ fringe) but nothing that really stands out even observing with the trained eye. The ‘Faster’ setting increases the overshoot a bit, making it easier to spot but by no means extreme. The ‘Ultra Fast’ setting increases this further, whilst the ‘Fastest’ setting changes the nature of the overshoot so it is very bright, colourful and eye-catching. Given that the ‘Fast’ setting is very effective at cutting out conventional trailing whilst introducing only a small amount of overshoot, we’d consider this optimal at 100Hz. Below we can see how things look with the refresh rate ramped up another notch, to 144Hz.

At 144Hz, above, there is a further focusing of the image with details more tightly focused. This indicates a further significant decrease in perceived blur due to eye movement. There is again varying amounts of trailing behind this, the nature of which is largely as it was at 100Hz. The ‘Fast’ setting again appears optimal here and in fact gives pretty much nothing to complain about. There is no real conventional trailing apparent and no obvious overshoot, only very faint traces which do little to affect overall perceived blur. In fact the performance here is slightly improved compared to the reference screens, even, giving an even ‘cleaner’ appearance. Both reference shots show more noticeable overshoot. For the XG2402 reference the performance is certainly very good, but if you look closely you can see a little conventional trailing and some ‘shadowy’ overshoot behind the UFO. We picked the dark background reference shot as it showcased this the best – compare to the top row (or indeed any row) of the XG240R test and you’ll see an already strong performance made even better.

Note: The ‘Monitor Hertz Cap’ did not function correctly on either the AMD or Nvidia GPU we tested. It did not change the Windows (or graphics driver) setting and instead simply caused obvious frame skipping and a generally uncomfortable experience if set to something lower than what Windows was set to. This sort of setting would be useful if it actually changed the refresh rate properly, but that didn’t seem to be the case. You can leave this at ‘Native(144Hz)’ and select any refresh rate available in Windows, your graphics driver or in-game without issue.

Responsiveness in games and movies

On Battlefield V the monitor performed exceptionally well in terms of responsiveness, where the frame rate kept pace with the 144Hz refresh rate. The monitor is displaying up to 2.4 times as much information every second as a 60Hz display, which has two beneficial effects. Firstly, it greatly enhanced the ‘connected feel’ when interacting with the game world. This describes a certain fluidity and precision, particularly when using the mouse, which is simply lacking at lower refresh rates regardless of input lag. The input lag of this model was very low, though, so this also aided this aspect of the experience. The other positive effect is a significant decrease in perceived blur, much as showcased with ‘Test UFO’. As also demonstrated there, there was very little to complain about in terms of pixel responsiveness. This was demonstrated on a broader scale on Battlefield V, with the monitor showcasing a broad range of very rapid pixel responses without significant overshoot. The end result was a very convincing 144Hz performance, with mere traces of overshoot in places that most users wouldn’t find bothersome or even notice in the first place. Competitively speaking there was really very little to complain about, with enemies being as easy to track and focus on as you’ll see on a 144Hz (sample and hold) monitor. Things were even better tuned than on the already impressive XG2402, as the small amount of ‘powdery trailing’ observed was cut back without being replaced by obvious overshoot.

We also tested Shadow of the Tomb Raider. Whilst not as fast-paced or generally as frantic, we still appreciated the 144Hz experience at high frame rates. There was a definite ‘glassy smoothness’ when interacting with the game world and manoeuvring Lara around, whilst details in the environment remained much sharper and better defined than on lower refresh rate models. There were no stand-out weaknesses with pixel responsiveness, so an exceptionally solid 144Hz performance here. We also observed movie content at various frame rates, with no clear weaknesses observed in terms of pixel responsiveness. The fluidity was limited by the frame rate of such content, particularly the more common ~24-30fps content, but there were no specific issues related to the monitor itself.

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.

FreeSync – the technology and activating it

AMD FreeSync is a variable refresh rate technology, an AMD-specific alternative to Nvidia G-SYNC. With this technology, the monitor adjusts its refresh rate dynamically, where possible, to match the frame rate being outputted by the GPU. Both the responsiveness article and the G-SYNC article linked to previously explore the importance of these two elements being synchronised. Essentially, a mismatch between the frame rate and refresh rate can cause stuttering (VSync on) or tearing and juddering (VSync off). An additional benefit of FreeSync is reduced latency compared to running with VSync on, within 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 also support the feature. The monitor must support ‘VESA Adaptive-Sync’ for at least one of its display connectors, as this is the protocol that FreeSync uses. The XG2402 supports FreeSync via DP 1.2a (‘DP 1.2a+’) as well as HDMI on compatible GPUs. AMD’s recent drivers include Radeon Settings, which makes activation of the technology very simple. It should be automatically enabled once the monitor is connected and ‘AMD FreeSync’ is set to ‘On’ on the ‘Gaming Settings’ section of the OSD. You can check its status by opening ‘AMD Radeon Settings’ and clicking 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. Note that the image below is just an example, taken from another display.



The ViewSonic supports a variable refresh rate range of 48 – 144Hz. That means that if the game is running between 48fps and 144fps, the monitor will adjust its refresh rate to match. When the frame rate rises above 144fps, the monitor will stay at 144Hz 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 144fps, 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 >144fps). 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 36fps, for example, the refresh rate would be 72Hz 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. 141fps) instead, avoiding any VSync latency penalty at frame rates near the ceiling of operation or tearing from frame rates rising above the refresh rate. Note that this model will show ‘FreeSync’ towards the top right of the OSD if the feature is enabled on the monitor. If you go to ‘Setup Menu’ – ‘Information’ in the OSD you will see the V. Frequency change in accordance with the frame rate if the feature is working correctly and the frame rate is fluctuating. Finally, it’s worth noting 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 tested a range of game titles with FreeSync active on the monitor. We found it worked much the same on all titles, indeed any issues that were isolated to one title would highlight a GPU driver or game issue rather than a monitor issue. We’ll therefore be focusing on a single title for this section; Battlefield V. This title offers sufficient flexibility with its graphics options for us to assess a full range of frame rates (and hence refresh rate) using this monitor and our AMD Radeon RX 580. Even using fairly modest settings, it was common to experience dips in frame rate below 144fps. Using a normal static refresh rate on the monitor (e.g. 144Hz without FreeSync active) would result in a frame rate and refresh rate mismatch. This gives obvious (to us) tearing and an associated juddering effect if VSync is disabled, or obvious (to us) stuttering if VSync is enabled. Even if the drops in frame rate were relatively minor, this mismatch is something we found very jarring. FreeSync prevented these mismatches and provided a much nicer ‘flow’ to the gameplay without such interruptions. Something that’s very nice to have as a user sensitive to tearing and stuttering. It’s worth bearing in mind that individual sensitivity to such things does vary, however.

If we increased the graphics settings such that frame rate hovered around 100fps (if we’re lucky), the absence of tearing or stuttering from frame rate and refresh rate mismatches with FreeSync active remained a very nice bonus. We also noticed a decrease in ‘connected feel’ and an increase in perceived blur due to the drop in frame rate, which is not something that is countered simply by matching up the refresh rate of the monitor with the frame rate of the content. With frame rate at the low triple digits to very high double digits, though, we still felt the monitor delivered a nice ‘connected feel’ and a decent reduction in perceived blur compared to significantly lower frame rates. If we increased graphics settings significantly and also bumped up the ‘resolution scale’ (rendering resolution) slider, frame rate dropped further. As it dipped well below 80fps and closer to 50 – 60fps, the ‘connected feel’ was greatly reduced and the perceived blur also significantly higher than at those nice triple-digit frame rates. But the lack of tearing and stuttering was again very noticeable, to us, and something we much appreciated.

A common observation we make with FreeSync models is that the pixel overdrive tends to be relatively well-tuned for high refresh rates (such as 144Hz), but not so well optimised for lower refresh rates (such as 80Hz or below). The voltage regulation required for these lower frame rates and hence the intensity of the pixel overdrive is very different to at higher frame rates, and FreeSync models rarely compensate for this drop properly. With that said, there was more noticeable overshoot at relatively low refresh rates (i.e. when frame rate drops, with FreeSync active) compared to higher ones. But this was by no means extreme and even at the very low end of the hardware range for FreeSync (48Hz/48fps) there was nothing we found too eye-catching in the way of overshoot. In fact, with the monitor set to a static 60Hz and set to our preferred ‘Fast’ setting, we found some stronger instances of overshoot than when running the monitor with FreeSync at ~60fps (~60Hz). The monitor was also able to cope well with dips below 48Hz (48fps) as it employed LFC, ensuring the refresh rate is kept to a multiple of the frame rate. There was a momentary and slight stutter of sorts when LFC activated or deactivated, but we didn’t find this jarring and most users wouldn’t notice this. It is just something that happens once the technology activates or deactivates, so would only be noticed if you frame rate is frequently hovering around 48fps. And even then it probably wouldn’t cause much bother.

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 XG240R, you need to connect the monitor up via DisplayPort and enable ‘AMD FreeSync’ in the ‘Gaming Settings’ 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. And indeed it did. We found the Nvidia Adaptive-Sync (G-SYNC compatible) experience much the same as using AMD FreeSync on this model without any specific additional issues. All of our observations regarding different refresh rate and frame rate ranges, somewhat increased overshoot as this reduces etc. therefore applies. Furthermore, the monitor supported an LFC-like technology and kept its refresh rate at a multiple of the frame rate if frame rate dipped below the floor of operation for VRR (48fps). 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 go to ‘Setup Menu’ – ‘Information’ in the OSD to see if the technology is working correctly whilst in game. You should see the V. Frequency change in accordance with the frame rate if the feature is working correctly and the frame rate is fluctuating.

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
Responsiveness

Conclusion

When it comes to highly responsive 24” gaming monitors, there is quite a range of models to choose from. Many of them actually use the same panel, which has been in production since 2011. There is of course more to a monitor than just a panel, and that’s why we poured a lot of praise over the ViewSonic XG2402 which put this panel to about as good use as we’ve seen. The XG240R presented an evolution of sorts, making a few tweaks and adding some new styling elements and related features. The OSD (On Screen Display) was re-worked, although the features themselves and the control system itself remained very familiar. The most notable change came in the form of the ‘ELITE RGB’ lighting feature, which provided a nice little rainbow effect on the wall behind the monitor. The colours and patterns could be customised using software, which was a nice touch. Although we would’ve liked to have seen a greater level of customisation through the OSD itself and also a higher brightness for the LEDs.

In terms of image quality things were very similar to the older model, which again comes down to the panel used. It retained excellent flexibility in the OSD, including multiple ways of fine-tuning gamma. It’s important to be able to do this (and it’s something many models using this panel lack, to this degree) as there is a huge amount of inter-unit variation when it comes to gamma behaviour on these panels. We were able to achieve decent tracking of the ‘2.2’ curve with some room to spare above if higher gamma was desired. Another area of variation with this panel comes from contrast. On our XG2402 we had a significant issue with static contrast as it was much lower than it should be. On the XG240R, it’s about as good as we’ve seen from this panel. Having gathered a lot of feedback, most units are fortunately more like our XG240R than XG2402 in that respect. The static contrast was not sufficient to give a great ‘inky’ depth to dark scenes, whilst the medium matte anti-glare screen surface gave a bit of a grainy look to lighter elements. So they didn’t appear all that smooth and didn’t really ‘pop’. But contrast was, overall, in-line with our expectations for a TN panel and was passable overall. There was no ‘IPS glow’ to spoil the experience, either, although the significant perceived gamma shifts did affect detail levels depending on which section of the screen you’re viewing.

Colour reproduction was helped tremendously by the appropriate gamma handling of the monitor, centrally. It avoided the ‘flooded’ or ‘washed out’ look that some models with this panel present, given their complete lack of flexibility in the OSD. Things appeared reasonably rich overall. The colour gamut was close to sRGB, so coupled with the screen surface things didn’t really ‘pop’ in the brilliant and vibrant way that they do on some models. Saturation was also affected by perceived gamma shifts, with a noticeable loss of saturation lower down and a deeper than intended look further up the screen. Even if the screen was set up for decent ‘2.2’ gamma tracking centrally. These shifts in saturation applies to a significant degree on all TN models. Although the particular panel used here exhibits somewhat stronger saturation loss lower down than some panels. Not a specific criticism of this model, but again a limitation of the panel used.

One particular area where the XG2402 really impressed us was responsiveness. And the XG240R didn’t disappoint in that respect, either. In fact it surprised us, because it seems that ViewSonic managed to eek out a little more pixel responsiveness using our preferred ‘Fast’ setting, without introducing a troublesome amount of extra overshoot. The XG2402 gave a remarkably solid 144Hz performance overall, but there was a little bit of ‘light powdery’ trailing in places from slightly slower than optimal pixel responses. Using a faster ‘Response Time’ setting (e.g. ‘Faster’ or above) simply gave strong overshoot as an unacceptable trade-off. The XG240R on the other hand as good as eliminated the ‘light powdery’ trailing without introducing a troublesome or particularly noticeable degree of overshoot. In fact we’re quite confident we’ll be using this as a reference for pixel responsiveness in many of our future reviews. Input lag was also nice and low, whilst the monitor provided a very effective Adaptive-Sync implementation. This allowed both AMD FreeSync to be used as well as ‘Nvidia G-SYNC compatible mode’ on GPUs that support it, combatting tearing and stuttering from frame and refresh rate mismatches. Although we’d consider things better tuned for higher refresh rates on this monitor than lower ones, the experience at the lower end of the variable refresh rate range was still good on this monitor. Without any particularly obnoxious overshoot or excessive conventional trailing.

Overall this monitor lived up to our expectations given our vast experience with the panel it used. It actually impressed us in a positive way with its pixel responsiveness, offering a slight improvement over the already very solid performance of its predecessor. This was also the first model we reviewed that we got to test Adaptive-Sync on an Nvidia GPU with, and we were happy to see it offered a very similar experience to FreeSync on our AMD GPU. Having a relatively affordable and exceptionally responsive monitor like this that offers a pretty solid variable refresh rate experience for both AMD and Nvidia GPU users is a very nice thing indeed. Whether these slight improvements in pixel responsiveness, the ‘stealthier’ appearance and ‘ELITE RGB’ lighting feature are enough to sway you over the older model is something you’ll have to consider for yourself. But taking this monitor on its own merit, it’s certainly a worthy choice for users who value strong responsiveness and still want reasonable image quality.

The bottom line; an excellent choice if responsiveness is your primary concern and you still want reasonable image quality – with one of the most comprehensive menu systems on the market.

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.