Acer Nitro VG270U P
Short Format Review
 

Default setup of the screen is pretty good with a fairly accurate gamma (2% deviance) and white point (5% deviance) which is just slightly too warm [detailed report]. There is good adjustment range from the backlight (52 to 329 cd/m²) as well for a range of ambient light conditions. The screen has a standard sRGB gamut only, and we measured a slight over-overage at 108% but nothing significant. This makes it easier to use the screen for more general uses, colour critical work etc where sRGB content is being viewed, although it does mean you lack the vividness and "pop" of colours that a wide gamut backlight would offer.

Contrast ratio was strong for an IPS-type panel at 1346:1 out of the box which was excellent, although after calibration adjustments this dropped a bit to a still respectable 1193:1. Our calibrated settings are listed in the table below [also see the detailed report], and our calibrated ICC profile is available here if you want to try it.

When it comes to gaming the VG270U P supports adaptive-sync allowing for variable refresh rates from compatible NVIDIA G-sync and AMD FreeSync cards, and helping systems cope with the varying frame rates likely to occur when powering the screen at its native 2560 x 1440 resolution and up to 144Hz refresh rate. The VRR range supported is 40 - 144Hz and you have to enable the 'FreeSync' option in the OSD for this to operate. We noticed that from our AMD system when you do enable that setting, the 'Over Drive' control is locked at the middle 'Normal' setting, although this didn't seem to be the case from our NVIDIA system, where the Over Drive setting was available even when FreeSync is enabled in the OSD, and G-sync is activated at the graphics card level.

With Over Drive setting at normal we had pretty mediocre response times across the range. As with many adaptive-sync screens, the response times are actually reduced as the refresh rate increases. This helps reduce any overshoot as the refresh rate increases, but results in slower response time and a reduction in the ability of the screen to keep up with the frame rate sadly. At 144Hz the average G2G response time was measured at 12.7ms which is not fast enough to keep up with the 144fps frame rate. As a result you get some additional smearing in motion. The motion clarity was moderate, and there was no severe ghosting or blurring to the image, it just wasn't as sharp or clear as many high refresh rate screens. There was at least no overshoot detectable in practice, and only a small amount measured down at 60Hz.

We also turned FreeSync off and measured the screen in the maximum 'Extreme' Over Drive mode. In this mode 60 - 100Hz refresh rates are pretty unusable due to very high levels of overshoot, forming obvious pale and dark halos behind moving objects especially at the lower refresh rate end. The overdrive impulse is being applied far to aggressively. For the upper end of the refresh rate range around 110 - 144Hz it is useable and there are low levels of overshoot visible. At max 144Hz there was very little overshoot at all, and the response times had been improved massively. Now measured at 6.0ms G2G average and being able to keep up well with the 144fps frame rate, we saw a much clearer and sharper moving image with much better motion clarity.

On AMD systems this mode seems to be only available if you disable FreeSync though but if you have a powerful system and can deliver in those upper refresh rate range, you may want to use this mode instead of FreeSync for optimal motion performance. If you're using an NVIDIA system you seem to be able to set this mode to Extreme if you want, even when using G-sync VRR. However, you will want to revert to 'Normal' mode if you're going to be struggling to power those higher refresh rates reliably, otherwise the overshoot is horrible at the lower end. Normal is probably the safer setting to support the full refresh rate range during VRR. Input lag of the screen was very low, with an approximate 0.5ms signal processing lag only which was very good.
 

The VG270U P features a motion blur reduction backlight as well, available via the 'VRB' (Visual Response Boost) setting in the OSD menu. This strobes the backlight off/on rapidly to help reduce the perceived motion blur in gaming. This is available at refresh rates of 85, 100 and 120Hz, but oddly not at the maximum native 144Hz. There are two settings for VRB, Normal and Extreme. When enabled, the screen becomes very dark. The brightness setting is remembered from your normal setup, so if you want to make it brighter you have to increase the OSD brightness level, but then you will have to reduce it back down when you turn VRB off which is a pain. Even at the maximum 100 brightness level, the luminance of the screen is very low, measured at a maximum of 49.8 cd/m² when using the Normal mode at 120Hz. You can get a few extra cd/m² by using the VRB mode at a lower refresh rate but in all cases the screen is really too dark with this feature enabled. It might be ok if you are gaming in a dark room and need a low luminance, but it's not very flexible. If we review the strobing behaviour we can see that the backlight strobing is in sync with the refresh rate, but the 'on' period of the strobe is very short, at 0.75ms. This results in potentially a sharper and clearer image in theory, but does result in the very low brightness we saw.

We took some pursuit camera photos in VRB mode showing the motion clarity in the top, middle and bottom areas of the screen. This method is designed to capture the level of motion blur that you would see in practice. You do have access to the Over Drive setting when VRB is enabled and these images were taken at 120Hz with Over Drive set to Extreme. The image is sharper with VRB enabled and tracking of the moving object across the screen is easier. In the top and central areas of the screen there is also fairly low strobe cross-talk, the trail behind the moving object. In the bottom region this is a lot more noticeable with a strong trail image. If you lower the Over Drive setting down to 'Normal' then the response times are reduced quite a lot, and this results in more noticeable trailing in VRB mode. We would recommend using VRB at 120Hz and with Over Drive set to 'Extreme' if you can.
 

Conclusion - The VG270U P provides a modestly priced option in the 1440p IPS 144Hz gaming monitor market and is available in several regions from Amazon (affiliate link). It provides some solid all round performance thanks to the IPS panel, including a decent factory setup and strong contrast ratio for this technology. The 1440p resolution is obviously very welcome compared to 1080p models in this size bracket. Its high refresh rate, low lag and support for FreeSync and G-sync makes it well suited to gaming on the most part although it struggles a little in terms of response times in some cases. You really have to push the Over Drive setting up to the maximum Extreme mode to get the best response times, but that's only really practical at the upper refresh rate range. Any drop below and you get too much overshoot, necessitating a switch to the Normal mode and some slower response times. The screen was a little lacking in other areas with only a basic tilt function from the stand, and it only offers a standard sRGB colour space as well so lacks the punch of some wider gamut screens for gaming and multimedia vividness. However, it was nice to see a few additional extras in the menu for gaming and overall the performance was pretty decent. The VRB mode performed quite well, but we felt it was far too dark to make it practical for most people sadly.

 

Testing and Results Explained

We will test and measure a range of aspects of these displays. By way of a brief explanation of what some of the results mean we thought we'd include this short guide:

Setup and Measurements Section

• Maximum and minimum brightness - the full range in which the backlight can be adjusted using the monitor's brightness control. At the upper end this can be important for gaming from a further distance, especially in brighter rooms and the daytime. At the lower end this can be important if you are using the screen up close for more general office-type work, especially in darker room conditions or at night.

• Recommended brightness setting - to achieve approx 120 cd/m², which is the recommended luminance for LCD monitors in normal lighting conditions

• Flicker free - independently tested and confirmed whether the screen is flicker free or not and without PWM at all brightness settings

• Default gamma - we aim for 2.2 which is the default for computer monitors, so will show the average achieved out of the box and the % deviance from our target

• Default white point (colour temperature) - we aim for 6500k which is the temperature of daylight, so will measure the default setup out of the box and include the % deviance from this target

• dE colour accuracy (relative to sRGB) - the default average dE measured out of the box. This is always compared with sRGB and so on wide gamut screens you would expect this to be less accurate given the wider colour space

• Contrast ratio - the default measured contrast ratio of the screen out of the box before any calibration or corrections

• sRGB emulation mode available - whether or not the screen features an sRGB emulation mode to reduce the colour gamut if needed. Only applicable if the screen is a wide gamut model, but some may not offer this feature leaving you limited to the full native gamut all the time

• sRGB coverage - measured when using the sRGB emulation mode (if available and applicable)

• dE colour accuracy - default colour accuracy measured when using the sRGB emulation mode

Calibrated Settings Section

• Recommended OSD settings - our calibrated settings to reach an optimal hardware setup, aiming for 2.2 gamma, 6500k white point, 120 cd/m² luminance and highest contrast ratio. You will find our calibrated ICC profile in the relevant section for each screen as well if you want to try it.

• Colour space and contrast - measured colour space (gamut) of the backlight relative to the sRGB colour space (including any over-coverage), and the DCI-P3 reference colour space. We also measure the post-calibration contrast ratio in case that has been impacted during the corrections.

Gaming Performance Section

We first of all test the screen visually in each of its available overdrive modes and at a range of refresh rates from 60Hz, all the way up to the maximum supported. This allows us to identify what appears to be optimal setting for each refresh rate and we can then measure the response times across a range of grey to grey (G2G) transitions using our oscilloscope setup. The table included shows then the average G2G response time measured at several refresh rates, along with the optimal overdrive setting we found. The overshoot level is then also rated in the table at each refresh rate. We will explain in the commentary if there are any considerations when using variable refresh rates (VRR) as well as talking about the overall performance our findings during all these tests.

At the maximum refresh rate of the screen we will also include our familiar more detailed response time measurements, which includes a wider range of transition measurements as well as some analysis of things like the refresh rate compliance. This identifies how many of the measured pixel transitions were fast enough to keep up with the frame rate of the screen. Ideally you'd want pixel response times to be consistently and reliably shorter than this refresh rate cycle, otherwise if they are slower it can lead to additional smearing and blurring on moving content.

In this section we will also include the measured input lag and look at any blur reduction backlight feature if it's available. The commentary in each section will provide more information if a blur reduction mode is available and how it operates.