Introduction

We've looked at quite a few gamer-orientated screens in the past. Technologies have improved over the last few years for sure and LCD monitors are attracting a new market of those who demand high end gaming experiences. First there was one of the first 120Hz compatible LCD's back in September 2009, the Samsung SM2233RZ, which offered support for NVIDIA's 3D stereoscopic gaming technology, as well as support for a 120Hz refresh rate. This marked a major step forward in gaming TFT's, now finally being able to support higher refresh rates natively and bringing about support for higher frame rates for even better gaming experiences. In January 2011 we also looked at BenQ's XL2410T which was co-designed with professional gamers and carried all kinds of fancy extras and features for gaming needs. The following year in February 2012 the replacement XL2420T brought other improvements and updates to meet growing demands of gamers out there. In the past we've also looked at a couple of screens rated with an ultra-low 1ms response time, including the ViewSonic VX2739wm and Iiyama G2773HS. Obviously steps are being taken by manufacturers to improve their gaming displays and this is of course very welcome.

Asus have been the first to now offer another step-change in gaming support. Their 27" VG278HE which we have with us at the moment is one of the first in the World to offer support for an extended 144Hz refresh rate. It offers high frame rates, support for 3D Vision 2 from NVIDIA, LightBoost technology and several other features which are making this a popular choice for gamers. We will put the VG278HE through its paces in this review and see how it performs in our tests.

Specifications and Features

The following table gives detailed information about the specs of the screen:

Manufacturers website link: Asus

The VG278HE offers a reasonable set of features. There are connections for analogue VGA, DVI (dual link) and HDMI provided. All three can support the full native 1920 x 1080 resolution, and the DL-DVI can support the bandwidth to deliver the 120 / 144Hz refresh rates. Good to see HDMI included for connection of external games consoles and DVD / Blu-ray players as well, although DisplayPort has been left off this screen unfortunately. The screen offers 2x 3W integrated stereo speakers along with an audio input and output connection. There aren't any USB ports here which can be very useful we think. Some of the more high end features have of course been left off as this is a gamer-orientated screen as opposed to being aimed at professional users.

Below is a summary of the features and connections of the screen:

The Asus VG278HE comes in an all-black design with glossy plastics used for the bezel, stand and base. The bezel is of a moderate thickness, measuring ~21mm along the top and sides, and ~24 along the bottom edge. There is a grey-coloured 'HDMI' logo in the bottom left hand corner and shiny silver coloured 'Asus' logo in the middle of the bottom edge. In the bottom right hand corner are small light grey labels for the OSD control buttons, which are situated along the underside edge of the screen (which we will look at in a moment). Overall, nothing fancy but it does the job.

Above: back views of the screen. Click for larger versions

The back of the screen is encased in a matte black plastic cover as shown above. There is a large Asus logo etched into the back at the top, and the arm for the stand screws into place in the middle. This can be removed if you want to VESA 100 wall/arm mount the display instead.

Above: cable tidy clip (left) and rounded base (right). Click for larger versions

The back of the stand has a small cable tidy clip as shown above which is useful for keeping everything neat on your desk. The base of the stand is a round shape, again in a glossy black finish. It has a large 3D logo in the middle of it, and around the edge there is a small, subtle font explaining some of the features of the screen.

Above: OSD control buttons and labels. Click for larger versions

The OSD control buttons are located on the underneath edge of the bottom of the screen as shown above. They are easily found and controlled by touch, and the small labels on the front of the screen make it clear what each button is doing and where they are. At the far right hand end is the power on/off button which glows blue during normal use and amber in standby.

Above: Side view showing full tilt range. Click for larger versions

The screen has a reasonably thin profile thanks to the use of W-LED backlighting. There is a reasonable, but not massive tilt range available which is smooth and easy to use.

Above: Front view showing full height adjustment range. Click for larger versions

The screen also offers a height adjustment which is also smooth and easy to use. According to the spec this offers a 110mm adjustment range but we measured it at 100mm in practice. At the lowest position the bottom edge of the screen is ~50mm above the height of the desk, and at the maximum height position it is ~150mm. There is also a side to side swivel adjustment which moves the whole screen side to side and is stiff to use unfortunately. No rotation function is provided on this model.

OSD Menu

Above: views of OSD operational buttons

1. Power On
2. Hold Menu and don't let go
3. Unplug the power lead from the back
4. Re-insert the power lead after 2 seconds or more
5. Wait until the input selection message has finished displaying
6. Release Menu
7. Pressing Menu again brings up normal OSD but there is a now an "F" at the bottom which is the factory section

Power Consumption

In terms of power consumption the manufacturers spec states typical usage of <65W and in standby the screen apparently uses <1W.

We tested this ourselves and found that out of the box the screen used 33.4W of power while at its default brightness setting. At the maximum brightness level the screen used 34.1W of power, and at the lowest setting this was measured at 17.0W. Once calibrated we had reached a power consumption of 25.4W which had been once the screen had been set to achieve a luminance of 120 cd/m². During standby the screen uses 1.4W of power. We have plotted the results of these measurements on the graph below:

Panel and Backlighting

Panel and Colour Depth

The Asus VG278HE utilises a Chi Mei Innolux (CMI) M270HHF-L10 TN Film panel which is capable of producing 16.7 million colours with a 6-bit colour depth and additional Frame Rate Control (FRC) stage (6-bit + FRC). The panel is confirmed when accessing the factory menu as shown below.

Panel Coating

The screen coating on the VG278HE is a light Anti-Glare (AG) offering, common to TN Film matrices. It is not overly aggressive or grainy in appearance, but still provides the anti-glare properties to help avoid unwanted reflections.
 

Backlighting and Colour Gamut

The screen uses a White-LED (W-LED) backlight unit which has become very popular in today's market. This helps reduce power consumption compared with older CCFL backlight units and brings about some environmental benefits as well. The W-LED unit offers a standard colour gamut which is approximately equal to the sRGB colour space (equating to ~72% NTSC as well). Anyone wanting to work with wider colour spaces would need to consider wide gamut CCFL screens, or perhaps the new range of GB-LED displays.

PWM Flicker Tests at Various Backlight Brightness Settings

We tested the screen to establish the methods used to control backlight dimming. Our in depth article talks in more details about a common method used for this which is called Pulse Width Modulation (PWM). Previously we have used a camera based method as described in the article to capture results at brightness settings of 100, 50 and 0. We now have a more advanced photosensor +  oscilloscope system which will allow us to measure backlight cycling with more accuracy and ultimately more ease.

These tests allow us to establish 1) whether PWM is being used to control the backlight, 2) the frequency at which this operates if used, and 3) whether a flicker may be introduced or potentially noticeable at certain settings. The higher this frequency, the less likely you are to see artefacts and flicker. The duty cycle (the time for which the backlight is on) is also important and the shorter the duty cycle, the more potential there is that you may see flicker. Please remember that not every user would notice a flicker from the backlight but it is something to be wary of. It is also a hard thing to quantify as it is very subjective when talking about whether a user may or may not experience the side effects. We are able to at least measure the frequency of the backlight using this method and tell you whether the duty cycle is sufficiently short at certain settings that it may introduce a flicker to those sensitive to it.

60Hz Refresh Rate

100%
 

Something to be wary of when running the VG278HE in 60Hz mode is that the screen actually operates internally at 120Hz and simply shows the same (60Hz) image twice in a row. This has no bearing on image smoothness though. It seems also that each of these two images is being separately dimmed, and you can see this split in the sample image above, taken at 100% brightness and 60Hz refresh rate. In this example at 100% brightness part A is not being dimmed at all, but part B is. PWM is active even at 100% brightness it seems although the modulation (difference between the two brightness points) is very low.

100%                                                                                   90%

50%                                                                                   35%

0%

As you can see from the above, as you dim the backlight from 100% down to 50% only image B is being dimmed still, with image A remaining constantly bright. Below a setting of 40% image A starts to be dimmed as well, progressively more so as you reach towards 0%. At this refresh rate we measured a low PWM frequency of 120Hz which could well introduce a noticeable flicker to the user as that is particularly low for PWM dimming.

This is how it appears when the photo method is used to measure PWM dimming at 60Hz refresh rate.

120Hz Refresh Rate

When operating at a 120Hz refresh rate the frame doubling is no longer happening internally and so you see a more constant and traditional PWM dimming. Again this is active to a small degree even at 100% brightness with a low modulation. This modulation increases to a point and then from there the duty cycle gets progressively shorter to aid further dimming as you reach towards 0%. We measured a PWM frequency of 360Hz when operating at this refresh rate.

  100%                                                50%                                                     0%

144Hz Refresh Rate

Again the PWM dimming is used when at the maximum 144Hz refresh rate and we measured a frequency of 432Hz in this mode. This is a reasonably high PWM frequency and may not introduce as much flicker as some lower frequency screens. We would suggest running the screen at its native maximum 144Hz refresh rate whenever possible, not only for the obvious gaming advantages, but to also help reduce possible PWM-related flicker issues.

Testing Methodology

An important thing to consider for most users is how a screen will perform out of the box and with some basic manual adjustments. Since most users won't have access to hardware colorimeter tools, it is important to understand how the screen is going to perform in terms of colour accuracy for the average user.

I restored my graphics card to default settings and disabled any previously active ICC profiles and gamma corrections. The screen was tested at default factory settings using the DVI interface, and analysed using an X-rite i1 Pro Spectrophotometer (not to be confused with the new i1 Display Pro colorimeter) combined with LaCie's Blue Eye Pro software suite. An NEC branded and customised X-rite i1 Display 2 colorimeter was also used to verify the black point and contrast ratio since the i1 Pro is less reliable at the darker end.

Targets for these tests are as follows:

• CIE Diagram - validates the colour space covered by the monitors backlighting in a 2D view, with the black triangle representing the displays gamut, and other reference colour spaces shown for comparison

• Gamma - we aim for 2.2 which is the default for computer monitors

• Colour temperature / white point - we aim for 6500k which is the temperature of daylight

• Luminance - we aim for 120 cd/m², which is the recommended luminance for LCD monitors in normal lighting conditions

• Black depth - we aim for as low as possible to maximise shadow detail and to offer us the best contrast ratio

• Contrast ratio - we aim for as high as possible. Any dynamic contrast ratio controls are turned off here if present

• dE average / maximum - as low as possible. If DeltaE >3, the color displayed is significantly different from the theoretical one, meaning that the difference will be perceptible to the viewer. If DeltaE <2, LaCie considers the calibration a success; there remains a slight difference, but it is barely undetectable. If DeltaE < 1, the color fidelity is excellent.

Default Performance and Setup

Default settings of the screen were as follows:

Asus VG278HE - Default Factory Settings, Standard Mode

 

The screen comes out of the box in the 'standard' preset mode ('Splendid' menu). When you first turn it on you immediately notice that the screen is very bright (default 90% setting) and the colours and image look very washed out. The gamma appears to be quite a long way off and the image doesn't look very good at all to be honest. This seems an odd default setup, but perhaps nothing has really been done in the factory.

The CIE diagram on the left of the top image confirms that the monitors colour gamut (black triangle) matches the sRGB colour space pretty well, giving only small amounts of over-coverage in some blues and greens but nothing significant at all. As you can see from the above table the gamma is well out, with a 1.7 average (24% out from our target of 2.2). This is especially low in lighter grey shades where it is as low as 1.06. This is why the image looks overly washed out and bleached. White point was at least very close to our target, being measured at 6633k (2% out). As you could tell with the naked eye, the screen was far too bright and we measured a luminance of 254 cd/m², and a black depth of 0.26 cd/m². The resulting 969:1 static contrast ratio was good, but with the gamma so far off this didn't produce very desirable images. Colour accuracy was also very poor, with a dE average of 7.5, and a maximum of 20.4. Clearly some kind of calibration is needed to get the screen set up better and the out-of-the-box performance was very disappointing really. I know this is primarily a gamers screen but this really was badly set up from the factory. Testing the screen with various colour gradients showed no visible sign of banding, although there was some gradation in darker tones and you could detect the Frame Rate Control (FRC) algorithm if you looked very closely.

Asus VG278HE - Default Settings, sRGB Mode

   

We also tested the default performance in the defined sRGB Splendid mode. Interestingly this seemed to alter the colour space coverage a little, seemingly moving the screen slightly further away from the sRGB reference as shown in the CIE diagram. Thankfully though in this mode the image quality improved quite drastically, becoming less bright and less washed out as you switched to it.

The tests confirmed that gamma was now much closer to the target, with an average of 2.3 and a smaller 5% deviance. White point was however a little too cool now at 7099k, being 9% out from our 6500k target. Luminance was a more comfortable, but still too bright at 178 cd/m², and the brightness setting was now locked in the OSD menu in this mode. Contrast ratio was not as good as before with a figure of only 680:1 obtained. Colour accuracy was much better though with a 2.3 dE average, 4.8 maximum. This mode obviously provided a better image quality out of the box but unfortunately it leaves the user with no control over the settings, including brightness, and so is still too bright. The contrast ratio is negatively impacted as well, so we will hope to obtain something better through a calibration process for day to day use.

Calibration Results

We used the X-rite i1 Pro spectrophotometer combined with the LaCie Blue Eye Pro software package to calibrate the screen at a software level and achieve these results and reports. An NEC branded and customised X-rite i1 Display 2 was used to validate the black depth and contrast ratios due to lower end limitations of the i1 Pro device. The screen does not feature any hardware level calibration support.

Asus VG278HE - Calibrated Settings

   

We stuck to the standard preset mode where you have full access to the brightness, contrast and RGB settings. Adjustments were made to the monitors OSD in line with the settings listed above which were obtained through the guidance steps of the process. This allowed us to reach an optimum hardware starting point to help retain tonal values as much as possible before the software profiling took place at a graphics card LUT level.

The calibration was a great success. To the naked eye we had now greatly improved the image appearance, getting rid of the washed out look, reducing the brightness and considerably helping with the colours. The validation report above confirms targets for gamma, white point and luminance were all met very nicely now with 0% deviance for each. The resulting static contrast ratio or 799:1 was decent enough for a TN Film panel, and keep in mind was now operating at a much better gamma. Colour accuracy was also very good with average dE or 0.6 and maximum of only 1.4. LaCie would consider colour fidelity to be excellent overall. Some banding was introduced to colour gradients as a result of the LUT corrections but that it is be expected when the starting point was so poorly set up.

You can use our settings and try our calibrated ICC profile if you wish, which are available in our ICC profile database. Keep in mind that results will vary from one screen to another and from one computer / graphics card to another.

Calibration Performance Comparisons

The comparisons made in this section try to give you a better view of how each screen performs, particularly out of the box which is what is going to matter to most consumers. When comparing the default factory settings for each monitor it is important to take into account several measurement areas - gamma, white point and colour accuracy. There's no point having a low dE colour accuracy figure if the gamma curve is way off for instance. A good factory calibration requires all 3 to be well set up. We have deliberately not included luminance in this comparison since this is normally far too high by default on every screen. However, that is very easily controlled through the brightness setting (on most screens) and should not impact the other areas being measured anyway. It is easy enough to obtain a suitable luminance for your working conditions and individual preferences, but a reliable factory setup in gamma, white point and colour accuracy is important and not as easy to change accurately without a calibration tool.

From these comparisons we can also compare the calibrated colour accuracy, black depth and contrast ratio. After a calibration the gamma, white point and luminance should all be at their desired targets.

Default setup of the VG278HE was disappointing unfortunately. The gamma curve was miles off the desired 2.2, with a 24% deviance (1.7 gamma average). Colour accuracy was also very poor with dE average of 7.5. The only thing which was well set up was the white point which was actually very close to the desired 6500k (only 2% out at 6633k).

We had seen similar poor default setup of gamma and colour accuracy from other gaming screens we have tested such as the Iiyama G2773HS and BenQ XL2420T. This is obviously not a prime concern of manufacturers when it comes to gaming displays, and I suppose some people may actually prefer the different gamma setup and accentuated colours for gaming. When it comes to accuracy and uses of the screen day to day it is not desirable though. Other lower cost 27" models with IPS panels such as the AOC i2757Fm and Dell S2740L had better default setups, but are more aimed at general use than specifically gaming.

The calibrated black depth and contrast ratio of the VG278HE were reasonable for a TN Film panel. At 799:1 the contrast ratio was very similar to that achieved with the Iiyama G2773HS (788:1) and ViewSonic VX2739wm (807:1), both using similar TN Film panels from CMI (formerly CMO). In fact the Iiyama G2773HS uses the same panel as this Asus VG278HE. We have seen some IPS panels reach nearer to 1000:1 contrast ratio, and AMVA variants can reach much higher still, between 2000:1 and 3000:1. All in all the contrast ratio should be adequate for most uses.

Contrast Stability and Brightness

The luminance range of the screen was excellent. At the top end the panel reached a high 262.80 cd/m² which was only a little short of the specified maximum luminance of 300 cd/m², and should be more than most users would need as an upper limit anyway. At the lower adjustment end it could reach down to a pretty low 67.91 cd/m². This meant the screen should be fine even in darkened room conditions, and for those who like to run at a lower luminance setting. A brightness setting of ~18 should return you a default luminance of around 120 cd/m² as well. Black point ranged from 0.26 cd/m² down to 0.07 cd/m² with the backlight adjustments.

We have plotted the luminance trend on the graph above. The screen behaves as it should, with a reduction in the backlight intensity controlled by the reduction in the OSD brightness setting. This was not a linear relationship though. As you can see from the graph the settings of 40 and below controlled a slightly steeper adjustment range. As we discussed earlier on in the review, the dimming of the backlight is achieved through the use of Pulse Width Modulation (PWM) and from a brightness setting of 40 and below the second image is dimmed as well as the first (See the PWM tests for more information about this). That explains the steeper curve from 40 downwards on the above luminance graph.

Average contrast ratio in the standard default preset mode was measured was 1012:1 which was good for a TN Film panel really. This was however measured in the default screen state where gamma was way off and the appearance of the screen was not pleasant. After calibration this contrast ratio would be lower, but it was pleasing to see that it was fairly stable across the brightness adjustment range. There was some variance at the lower end, again seemingly from 40 downwards where the PWM dimming technique changed.

Dynamic Contrast

We tested the DCR feature in all four modes where it was available. The feature didn't do anything at all in any of the modes in practice, even when switching between the two extremes of almost all-white and almost all-black content. When switching to a 100% totally black image the backlight is actually turned off after about 1 second, so this is where the crazy 50 million:1 spec comes from, but is of course pointless in practice. All this does is allow for exaggerated laboratory testing and the resulting specs, but in  normal use, the DCR is pointless.

Viewing Angles

Above: Viewing angles shown from front and side, and  from above and below. Click for larger image

Viewing angles of the VG278HE were as you might expect from a TN Film panel. Unfortunately this panel technology is inherently poor in this field, and so viewing angles are far more restrictive than other competing technologies like IPS, PLS and VA. Although the manufacturer will quote a viewing angle of 170 / 160 (a classic indication that a TN Film panel is being used by the way if in doubt), in practice there are some obvious contrast and colour tone shifts horizontally, and especially vertically.

As you move your head from side to side in a horizontal plane, there is a contrast shift and the image becomes lighter and a slight yellow hue is introduced. As you move to a wider angle the image can become darker and a darker and slightly pink colour tint is introduced as you can see from the above photos. Vertically the fields of view are more restrictive still. From above the image becomes pale and washed out, while from below there is a characteristic TN Film darkening of the image. Unfortunately vertically the viewing angles will introduce noticeable shifts in the contrast and colour tone of the image which mean that for any colour critical work it is not really very well suited. TN Film panels have long suffered from these restrictive viewing angles due to the nature of their pixel structure. They are still fine for a single user for general use and certainly the TN Film panels offer their advantages when it comes to pixel response times and gaming. If however, you were hoping to do any colour critical or photography work you may find these shifts in the appearance of the image difficult. There is also the added issue of the poor default colour setup to deal with on this screen as well. An IPS panel would probably be a wiser choice if you were looking for a screen with much wider viewing angles but having said that you are probably mainly interested in gaming if you are considering this screen.

Above: View of an all black screen from the side. Click for larger version

On a black image there is a slight pale grey tint introduced to the image when viewed from a wide angle. This isn't too severe and shouldn't present any real problems in practice.

Panel Uniformity

We wanted to test here how uniform the brightness and colour temperature was across the screen, as well as identify any leakage from the backlight in dark lighting conditions. First of all measurements of the luminance were taken at 35 points across the panel on a pure white background. The measurements for luminance were taken using BasICColor's calibration software package, combined with the NEC customised X-rite i1 Display 2 colorimeter. Measurements for colour temperature (white point) were taken using BasICColor software and the i1 Pro spectrophotometer which can more accurately measure white points of different backlighting technologies. A camera was then used to capture any backlight leakage evident from an all-black screen in a darkened room.

The below uniformity diagram shows the difference, as a percentage, between the luminance recorded at each point on the screen, as compared with the central reference point of a calibrated 120 cd/m². This is the desired level of luminance for an LCD screen in normal lighting conditions, and  the below shows the variance in the luminance across the screen compared with this point. For colour temperature uniformity we leave all settings at default in the OSD menu and ensure no ICC profile is active. Again the uniformity is expressed as a percentage deviation from the central measurement of the screen.

It is worth noting that panel uniformity can vary from one screen to another, and can depend on manufacturing lines, screen transport and other local factors. This is only a guide of the uniformity of the sample screen we have for review. The U2413 features a uniformity compensation feature which we will test here as well, but first of all we left this setting off.

Luminance Uniformity

Uniformity of Luminance

The luminance uniformity of the VG278HE was very good really. There was some slight deviations in upper parts of the left and right hand edges where luminance dropped down by ~14% maximum (104 cd/m² being the lowest reading). The lower half of the screen showed a good uniformity, and overall ~95% of the screen was within 10% deviance of the central point which was very good. An impressive result really considering this isn't a high-end professional screen or anything.

Colour Temperature / White Point Uniformity

We also carried out our tests in this area to establish how uniform the colour was across the screen. We measured the white point (colour temperature) deviance compared with a central measurement point at default settings.

Uniformity of White Point / Colour Temperature

As you can see, the colour temperature was uniform across the panel with only small deviations across the screen. There was a maximum of 3.4% deviance in the top left hand corner, but this was a very small difference. The left hand part of the screen was a maximum of 5.7% different to the right hand part of the screen with a 381k difference in white point. Only a slight variation overall which should not present a problem in normal use. The restrictive viewing angles of the TN Film panel would be more of a concern I expect for any colour critical work.

Backlight Leakage

Above: All black screen in a darkened room. Click for larger version

As usual we also tested the screen with an all black image and in a darkened room. A camera was used to capture the result. Overall there was no significant backlight bleed from this panel, although there did seem to be a very slight bleed around all 4 edges as you can make out in the above photo. This was only a very thin line of light and shouldn't present any problems in normal uses really.

General and Office Applications

The 1920 x 1080 resolution and 27" screen size give a decent area in which to work and offers a larger font size than a smaller screen featuring the same resolution. This means it is easier on the eye than for instance a 21.5" or 23" model with a 1920 x 1080 resolution and offers a larger 0.311 mm pixel pitch. The resolution is still perfectly fine for side by side working but of course the res is quite a lot lower than some other competing 27" models with their ultra-high 2560 x 1440 resolution panels.

The coating used on the TN Film panel is a light Anti-glare (AG) solution and so white office backgrounds do not look overly grainy or dirty as they can on some screens where a more aggressive AG is used. The AG coating also ensures minimal reflections which is useful for office applications. The viewing angles of the TN Film panel technology are the technology's main weakness nowadays and you can notice acute contrast and colour tone shifts as you change your line or sight. The viewing angles are particularly restrictive in the vertical plain so be wary if you need to do any colour matching or work with photos. The W-LED backlight unit offers a colour space approximately covering the sRGB colour space which is fine for the majority of users.

For general use the default setup of the screen is poor unfortunately and so you will certainly want to try and calibrate it in some way to get something more comfortable. You may want to follow our calibration process (and maybe also try our calibrated ICC profiles) to get a better setup, even without a colorimeter of your own. A colorimeter of your own would of course allow for better correction for these kind of uses, especially to correct the gamma curve.

There is no specific 'text' or 'internet' type mode available from the preset menu so you will probably want to try and set up the standard mode to your liking. The brightness control provides a quick and easy method for altering the luminance of the display to meet changing lighting conditions. The brightness control also affords you a very good range of adjustments for the backlight, allowing you to control the luminance from ~263 to 68 cd/m². This lower setting should be fine for most users, even those wanting to use the screen in low ambient lighting conditions. Pulse Width Modulation (PWM) is unfortunately used for backlight dimming so anyone who is sensitive to PWM related flickering need to be careful. Running the screen at the higher 144Hz refresh rate does help improve the PWM frequency though.

The screen doesn't have any USB ports which is a shame as those can be very useful in office environments. There are 2x 3W integrated speakers which may be useful for some people for the occasional office noise, YouTube clip or Mp3. No other advanced features such as ambient light sensors or card readers are featured. The stand does provide a good range of adjustments which is good, helping you obtain a comfortable position for your working environment. There is no rotate function though in case you were wanting to work in portrait mode for anything. The D-sub connection provides a decent image quality as well although digital DVI was a little sharper and should be used where possible.

Above: photo of text at 1920 x 1080 (top) and 1600 x 900 (bottom)

The screen is designed to run at its native resolution of 1920 x 1080. However, if you want you are able to run the screen outside of this resolution. We tested the screen at a lower 1600 x 900 resolution to see how the screen handles the interpolation of the resolution, while maintaining the same aspect ratio of 16:19. At native resolution the text was very sharp as you can see from the top photograph. When you switch to a lower resolution the text is larger of course and a lot of the sharpness is lost. The image is quite blurry and to quite a significant extent. We would recommend native resolution wherever possible for maximum picture quality and screen real-estate.

Responsiveness and Gaming

The VG278HE is rated by Asus as having a 2ms G2G response time which implies the use of overdrive / response time compensation (RTC) technology, used to boost pixel transitions across grey to grey changes. The part being used is the Chi Mei Innolux (CMI) M270HHF-L10 TN Film panel. Have a read about response time in our specs section if you need additional information about this measurement.

Being a gamer-orientated screen the VG2787HE offers a control for the overdrive impulse via the OSD menu, under the 'Trace Free' setting. By default this is set at 60, but has options for 0, 20, 40, 60, 80 and 100. This is designed to give the user control over how aggressively the RTC impulse is applied, helping to reduce blurring in gaming but at the same time being customisable in case overshoot artefacts become too troublesome.

We will first test the screen using our new response time testing method. This uses an oscilloscope and photosensor to measure the pixel response times across a series of different transitions, in the full range from 0 (black) to 255 (white). This will give us a realistic view of how the monitor performs in real life, as opposed to being reliant only on a manufacturers spec. We can work out the response times for changing between many different shades, calculate the maximum, minimum and average grey to grey (G2G) response times, and provide an evaluation of any overshoot present on the monitor.

We use an ETC M526 oscilloscope for these measurements along with a custom photosensor device. Have a read of our response time measurement article for a full explanation of the testing methodology and reported data.
 

Trace Free

First of all we wanted to do some tests of the Trace Free option within the OSD to determine what impact it has on overall response time and any resulting artefacts and overshoot. We took measurements across 12 different transitions in each of the 6 Trace Free modes along with measurements of any overshoot produced. From there we can calculate the average G2G response time in each mode (for the 12 changes measured) and the average RTC error percentage.

For now we left the screen at a 60Hz refresh rate as we are just looking at this stage to establish the differences between each Trace Free setting. Once we have established the optimum setting we will carry out further tests on the response time to give an even more accurate view (based on 30 transitions) and then also test the screen at the higher 144Hz refresh rate.

The Trace Free settings of 0 and 20 still offered very low response times on the whole, with an average of 6 and 5.5 ms respectively. This was very impressive really and this is even at the lowest RTC levels. Some of the grey to grey transitions were slower (up to 10.9ms maximum) than the changes from and to the extremes of either black (0) or white (255). The RTC impulse was not being applied much at all in these settings and so was not impacting the G2G response times much. No overshoot was produced at these settings though as a result of the light RTC impulse which was pleasing.

The Trace Free option of 40 resulted in a slightly faster response time again with a 3.9ms average. The G2G transitions were now improved quite a lot (e.g. 0 - 150 and 50 - 150). There was some small overshoot introduced in some cases where G2G transitions had been boosted, but many pixel changes still showed no overshoot at all. Where the overshoot was picked out, it was slight and should not present any real issue in practice.

The default Trace Free setting of 60 improved response times slightly more again with a 3.4ms G2G average being measured in this selection of transitions. The overshoot was increased slightly but overall it was not too severe at all. In practice we did feel this setting returned a slightly better image quality in fast moving scenes, and the overshoot was not problematic and fairly minimal. This did seem to be the optimum setting for gaming and so we will conduct some more thorough tests in a moment at Trace Free 60, including at the full 144Hz refresh rate. For movies and slower action games, a Trace Free setting of 40 or 20 may be slightly better as the response time is still excellent, but any RTC overshoot is pretty much eliminated. Worth experimenting with each setting to find the one you like the most for your uses.

The settings of 80 and 100 improved the response time slightly to 2.9ms average, but the RTC errors started to become more problematic unfortunately. You could notice more trailing in some moving scenes which could be distracting. For the small improvement in response time we didn't feel it was worth it for the increased overshoot personally.

Trace Free = 60, 60Hz Refresh

Now that we've established that the setting of 60 delivered optimum performance for gaming we will complete our usual tests for response time in more detail. We now measured 30 different transitions to give an even more complete view of the response times of the matrix. For now we remained at 60Hz refresh rate.

On the whole the pixel transitions were very fast. The average G2G response time was measured at 4.1ms which was slower than the specified 2ms G2G from the manufacturer, but still very respectable indeed. Some of the wider dark to light grey changes (0-200, 50-200, 100-200) were a little slower at around 8 - 9ms. The average G2G rise time (changes from dark to light shades) was slower than the average G2G fall time (changes from light to dark shades), about double the time in fact, but both were very good. The response times of the VG278HE were very impressive and it should be perfectly fine for fast gaming.

The RTC overshoot was also kept pretty low overall. A few transitions showed some fairly significant overshoot (mostly changes from black to grey shades) but the rest of the changes were smooth and showed very few problems. The average RTC error across all the changes measured was 3.4% which was good. The Trace Free 60 setting did seem to offer the smoothest game play in practice and the small amounts of overshoot are forgivable for what is a very fast and responsive panel we felt.

Trace Free = 60, 144Hz Refresh

We also tested the screen at the Trace Free 60 setting, but with the refresh rate set at the maximum 144Hz.

As you can see the overall responsiveness didn't change massively, although the average G2G response time had dropped ever so slightly from 4.1ms to 3.9ms. The fall times (changes from light to dark shades) were still twice as fast as the rise times (changes from dark to light). Overall the refresh rate made little change at all to the pixel response times of the panel as you'd expect. The frame rate was much higher though of course, helping to provide smoother movement which was detectable even when simply dragging windows around your desktop. For gaming the increased refresh rate holds a very big advantage and really does help with the smoothness of the image and makes moving images much better.

The overshoot picture was very similar as well with an average RTC error of 3.4% overall. Again the 144Hz refresh rate seemed to have no impact on the level of overshoot. In practice while the images were no doubt smoother and faster than at 60Hz, if you looked very closely you could still see the signs of some overshoot.

Display Comparisons

The screen was also tested using the chase test in PixPerAn for the following display comparisons. As a reminder, a series of pictures are taken on the highest shutter speed and compared, with the best case example shown on the left, and worst case example on the right. This should only be used as a rough guide to comparative responsiveness but is handy for a comparison between different screens and technologies as well as a means to compare those screens we tested before the introduction of our oscilloscope method.

27" 2ms G2G Chi Mei Innolux TN Film +144Hz (Trace Free = 60)

In practice the Asus VG278HE showed very smooth motion as you would hope for from a gaming screen, and one which we've already established offers very low pixel response times. Movement was smooth and free from any ghosting or major blurring. There was some slight blurring of the image of course due to the nature of LCD screens but the moving image was sharp and clear really. In the right hand image you can see the overshoot more clearly. It is there in the left hand image as well, although not as pronounced. In this test the overshoot manifested itself by a pale trail behind the moving image. It wasn't too severe at all though. This was at Trace Free 60, and as you cycle between the other settings you can see the impact it has on response time. If you lower the setting down to 40, the visible overshoot disappears, although the image is ever so slightly more blurry. If you raise Trace Free above 60 the overshoot becomes more and more obvious.

27" 2ms G2G Chi Mei Innolux TN Film +144Hz (Trace Free = 60)

27" 1ms G2G Chi Mei Innolux TN Film + 120Hz (Over Drive = 0)

24" 2ms G2G AU Optronics TN Film + 120Hz (AMA = On)

We have provided a comparison of the VG278HE first of all against some of the other fast gaming screens we have tested. Both of these other models support 120Hz for improved frame rates and gaming experience. They are also TN Film based panels with response times quoted at 1 or 2ms G2G. As you can see the VG278HE performs very well in these comparisons, offering arguably the lowest levels of motion blur in practice. The Iiyama G2773HS uses the same CMI panel as the VG278HE and its performance was pretty similar really, perhaps a little slower in some cases. The BenQ XL2420T showed more noticeable overshoot in practice due to its more aggressive overdrive impulse when its AMA function was enabled. This took the form of a dark and pale trail as you can see in the images above.

27" 2ms G2G Chi Mei Innolux TN Film +144Hz (Trace Free = 60)

24" 7ms G2G LG.Display AH-IPS

27" 5ms G2G LG.Display AH-IPS (overdrive = medium)

27" 4ms G2G AU Optronics AMVA (AMA = Premium)

We have provided then a comparison of the VG278HE against 3 other 27" models, all sporting a 1920 x 1080 resolution, but this time using different panel technologies (and no support for 120 / 144Hz refresh rates). The IPS based Dell S2740L and AOC i2757Fm were slower in practice, but you would probably expect that considering we're comparing them with a gamer-orientated fast TN Film based screen here. The Dell showed a quite obvious dark overshoot in these tests and while the AOC was free from this problem, it did show more noticeable blurring. The BenQ GW2750HM is based on an AMVA panel, showing improvements compared with older generations of this AU Optronics technology, but still being slower (and with more overshoot) than the Asus VG278HE by a noticeable margin.

27" 2ms G2G Chi Mei Innolux TN Film +144Hz (Trace Free = 60)

27" 8ms G2G LG.Display AH-IPS

27" 5ms G2G Samsung PLS (Trace Free = 40)

27" 12ms G2G Samsung PLS (Response Time = Advanced)

27" 12ms G2G LG.Display H-IPS

We have also provided a comparison of the VG278HE against a range of popular 27" screens, this time all featuring a higher 2560 x 1440 resolution, and with IPS or PLS panel technology. Some of these screens performed very well in practice. The Dell U2713HM and Asus PB278Q showed very low levels of motion blur, although perhaps not quite as low overall as the Asus. They are also lacking any support of 120 / 144Hz refresh rates which will make a difference in gaming. The ViewSonic VP2770-LED was slightly slower with a more obvious blur, and the HP ZR2740w v2 was slightly slower again, with a less aggressive overdrive impulse being used as indicated also by its quoted response time.

The responsiveness of the VG278HE was excellent really. You have a wide range of options to play with in the Trace Free menu to tweak the performance as well. We found a setting of 60 (the default as it happens) to offer the optimum performance in our opinion, feeling slightly faster than a setting of 40, and avoiding too much overshoot which is accentuated too much as you raise the setting higher to 80 or 100. You may want to settle for TF 40 for movies or general use, but have a play with the control and see what you like. At a TF setting of 60, we measured a very low 4.1ms average G2G response time. There was some overshoot evident in some transitions but overall it was not too bad as long as you don't push TF to a higher level. With our PixPerAn tests we could see the subtle changes in practice as you switch between each level, and the slight pale overshoot was not too bad really at TF 60 and below.

Don't forget that one of the key selling points of this screen is its support of higher 120Hz and 144Hz refresh rates. In practice this does make a noticeable difference and should not be overlooked. While it doesn't change the fundamental behaviour of the pixels, the smoothness of movement is vastly improved, even when simply dragging windows around a desktop or moving your mouse pointer. The increased frame rate support is also very important to high end gamers, and those who play a lot of FPS particularly. Given the support of 120Hz+ here as well, the screen can also support NVIDIA's 3D Vision for stereoscopic content. So for those who might want to play 3D games this is another big benefit.

Additional Gaming Features (Updated 4 April 2013)

NVIDIA 3D Vision - The VG278HE is certified for 3D stereoscopic content through the latest NVIDIA 3D Vision 2. The screen's 120Hz+ refresh rate allows for 3D games and movies to be played using the appropriate active shutter glasses and NVIDIA kit (not supplied with the screen). The Dual-link DVI interface must be used to support the 120Hz+ refresh rate required for 3D content.

LightBoost - The screen also supports NVIDIA's LightBoost technology, designed to help improve brightness in 3D content. Asus' website states: "With the latest NVIDIA� 3D LightBoost Technology, enjoy twice the brightness of conventional 3D technology in 3D mode with zero increase in total energy consumption. It's perfect for dark-color games such as Metro 2033 and Batman: Arkham City. Additionally, the redesigned glasses bundled with NVIDIA� 3D LightBoost Technology features a 20-percent larger viewing lens, a light blocking visor for comfortable viewing and more comfortable - gamer-inspired design. "

An interesting additional benefit of LightBoost has been explored recently by http://www.blurbusters.com, where it is used in 2D mode to help reduce perceived motion blur in gaming and fast moving content. We have looked at this in more detail in our recent Motion Blur Reduction Backlights article. Please see that article for the full detail about how this technology can be used to reduce motion blur on the VG278HE and its benefits. We found it offered a significant benefit in fast moving content, reducing motion blur quite considerably.

Aspect Ratio Control - The screen offers hardware level aspect ratio control options within the 'image' subsection of the OSD menu.

 However these are very limited, with options only for "full" and "4:3" being available. There is no hardware level scaling support for 16:10 or 5:4 formats and no options to automatically detect and maintain the source aspect, or offer 1:1 pixel mapping. Being a 16:9 format screen natively, this might not be a massive problem as a lot of content will offer 16:9 format anyway. Also most graphics cards can control scaling from PC's anyway if working with anything outside of the ratios supported by the screen itself. However those using external devices and anything which doesn't operate in either 16:9 or 4:3 aspect may have problems. A little disappointing really as you might have hoped for a few more options here.

Preset Modes - There is a 'game' preset mode available from within the preset mode menu. This is brighter and more vivid than the standard mode and it gives you access to the dynamic contrast ratio if you want to use it, not that it really does anything in practice based on our tests. This mode might be useful if you want to set up a specific mode to be different to your day to day normal use profile as well.

Lag

For the full reviews of the models compared here and the dates they were written (and when screens were approximately released to the market), please see our full reviews index.

We have provided a comparison above against other models we have tested to give an indication between screens. Those shown with blue bars represent the total "display lag" as at the time of review we did not have access to an oscilloscope system to measure the response time element and provide an estimation of the signal processing. The screens tested more recently are split into two measurements which are based on our overall display lag tests (using SMTT) and the response time for half the average G2G response time, as measured by the oscilloscope. The response time is split from the overall display lag and shown on the graph as the green bar. From there, the signal processing (red bar) can be provided as a good estimation.

The Asus VG278HE was tested first of all at 60Hz refresh rate where we measured an overall display lag of 17.1ms average, ranging up to 20ms maximum. With the response time elements accounted for with ~2.05ms (half the average 4.1ms G2G response time) we can estimate a signal processing lag of ~15.05ms. When switching to 144Hz mode the overall display lag is reduced to 10.4ms average (11ms max). With 1.95ms accounted for in the response time element, the signal processing time is reduced significantly to 8.45ms. The overall lag of the screen is definitely better when running at 144Hz, so another reason to run the screen at this higher refresh rate. The screen can be categorised as CLASS 1 when at 144Hz.
 

Movies and Video

The following summarises the screens performance in video applications:

• 27" screen size makes it a reasonable option for an all-in-one multimedia screen, but being quite a bit smaller than modern LCD TV's of course.

• 16:9 aspect ratio is more well suited to videos than a 16:10 format screen, leaving smaller borders on DVD's and wide screen content which is commonly based on 16:9 aspect ratio.

• 1920 x 1080 resolution can support full 1080 HD resolution content.

• Digital interfaces support HDCP for any encrypted and protected content.

• As well as DVI there are also VGA and HDMI available which may be useful for connecting external devices. HDMI particularly useful given it is so widely used. A shame that DisplayPort wasn't included as well perhaps as it is becoming increasingly popular.

• Cables provided in the box for DL-DVI and VGA, but not HDMI.

• Light AG coating does not cause issues with reflections which glossy coatings can.

• Wide brightness range adjustment possible from the display, including high maximum luminance of ~263 cd/m² and a good minimum luminance of ~68 cd/m². This should afford you very good control for different lighting conditions.

• Black depth and contrast ratio are moderate for a TN Film panel at 799:1 after calibration. Shadow detail in darker scenes should not be lost though as this should be ok for most movie uses. Those wanting to watch a lot of dark content may want to think about a VA technology based screen.

• Dynamic contrast ratio available but does nothing on this model in real use.

• 'Movie' preset mode available if you want to set up a different mode for your movies.

• Excellent pixel responsiveness which should be able to handle fast moving scenes in movies without issue. Possibly some overshoot evident if you push the Trace Free setting too high so would suggest a setting of 40 for movies and videos is ideal.

• 120Hz+ refresh rate support allows for stereoscopic 3D content with relevant active shutter setup from NVIDIA. Viewing 3D movies is possible on this screen as a result.

• Limited range of hardware aspect ratio options with only 'full' and '4:3' available. May present problems with some external devices possibly.

• Viewing angles are limited due to the use of TN Film panel technology. May cause issues with gamma and contrast shift if you change your line of sight or have several people trying to see the screen at once. Not really an ideal technology for movies as a result of this viewing angle limitation.

• Reasonable range of ergonomic adjustments available from the stand. Should be easy to obtain a comfortable position for multiple users or if you want to sit further away from the screen for movie viewing.

• No major backlight leakage, with only a slight thin bright area along each edge which shouldn't prove a problem in normal use.

• 2x 3W integrated stereo speakers on this model and an audio connection. May be ok for some occasional video clips but probably not enough for any serious movie viewing.

• Picture in picture (PiP) and Picture By Picture (PbP) are not available on this model.

• For PAL sources, we have tested the screen and confirmed it will support the full native resolution at 50Hz refresh rate.
   

Conclusion

When trying to summarise the performance of the VG278HE we need to keep in mind the target audience and intended uses for this type of screen. We can't expect high end features such as hardware calibration, uniformity correction technologies or even a wide range of connections and extras like USB ports. The screen is aimed firmly at the gaming market and most gamers wouldn't need any of those features. They've been left off to help keep costs down which is no bad thing. The only things which were missing which could have perhaps been included were DisplayPort and USB connections we think.

We also can't expect the colour and image quality performance of high-end pro grade screens with their IPS and PLS panels. You have to live with the limitations of TN Film technology here, most notably when it comes to the restrictive viewing angles. The default setup of the screen was also poor as again accuracy is not a key concern for the intended audience, and contrast ratio will never reach the heights of a VA panel. We would have liked really to see more focus given to the factory setup as it was particularly poor here and the contrast ratio after calibration was ok, but not great for a TN Film panel.

While these limitations need to be accepted, the use of a TN Film panel does bring some significant advantages. The primary concern we're sure for anyone considering this screen is how it performs in games. In this area, it does very well indeed. It offers very low pixel response times and a wide range of user control to tweak the level of overdrive being applied. The support for 120Hz and 144Hz refresh rates brings a marked improvement compared with 60Hz displays, boosting the frame rates and overall smoothness of movement significantly. The screen also supports NVIDIA's 3D Vision 2 for those wanting to play any 3D content. Input lag was also sufficiently low when running at 144Hz refresh rate, which also had the added benefit of reducing the possible flicker from the PWM-dimming of the backlight. For gaming needs it is a very good option, perhaps lacking some of the frills of models like the BenQ XL2420T but providing excellent performance where it matters.