Asus ROG Strix XG27UCS review: Game at 4K 160Hz without breaking the bank

In March, Asus announced two new 27in gaming monitors. One, the ROG Strix XG27ACS, is a 1440p affair with a maximum refresh rate of 180Hz; the other, the ROG Strix XG27USC reviewed here, is a 4K display with a maximum refresh rate of 160Hz. Both use IPS panels and, resolution and refresh rate aside, are identical.

I’ve spent a couple of weeks testing the 4K model to see how it compares to the excellent 32in 144Hz LG UltraGear 32GR93U and have been very impressed. In fact, I’d go as far as saying it’s the most easily recommendable 4K gaming monitor on the market right now.

Asus ROG Strix XG27UCS review: What do you get for your money?

Physically, the XG27UCS is a run-of-the-mill black plastic affair. The 1440p model is available in white as well as black, though at a price premium, but sadly, the 4K model is only offered in black.

At the time of writing, the XG27ACS is available for the very attractive price of £260, while the XG27UCS can be yours for £539. Given their refresh rates and resolutions, both models represent very good value and look like appealing options for those wanting an affordable, high-quality IPS gaming display. 

The design is rather reserved by ROG standards. Tape over the unlit logos below the panel and on the base, and it could pass as an office monitor. There are no LEDs on the cabinet, but the 0.25in tripod thread at the top of the stand is still present and correct, so you can attach a bracket or clamp to mount a camera.

The bezels around the screen are not the thinnest you’ll ever encounter, but 10mm at the top and sides and 20mm at the bottom isn’t too bad considering the price point. At 210mm wide by 250mm deep, the base of the stand is impressively small and comes with a handy channel for holding your phone in landscape. Asus seems to be moving away from the visually impressive but rather impractical spindly three-leg bases that have recently typified its ROG monitor design, and I think that’s a good thing.

The stand attaches to the cabinet with a quick-release bracket under which sits a 100 x 100mm VESA bracket. Given that the cabinet weighs less than 4kg (the whole enchilada is 6.57kg), mounting it on a desk arm is a piece of cake.

The XG27UCS’s stand has plenty of adjustability, with 90-degree pivot to the left and right, 45 degrees of swivel to each side, tilt between -5 and +20 degrees and 120mm of height adjustment.

The monitor is controlled by a mini joystick and four push buttons on the right side of the cabinet rear. The controls are large, well-spaced, and easy to use, making navigation around the Asus ROG menu system straightforward. Two buttons can be user-assigned as shortcuts to any function you want immediate access to.

READ NEXT: Best monitors for home offices

Asus ROG Strix XG27UCS review: What connections does it have?

The range of I/O ports can most generously be described as minimalist, so all you get are three video inputs: HDMI 2.1, DisplayPort 1.4 and a USB-C port that supports DP Alt Mode video and 15W charging, and a 3.5mm audio jack.

Given that this is not a cheap monitor, there’s a strong argument that Asus should have fitted a couple of USB-A ports and perhaps even a USB-B, which could have added genuine KVM functionality. I admire Asus ROG’s dedication to the conceptual purity of a gaming monitor, but given the impressive all-around competence of the XG27UCS, the absence of such cheap and compact expansion facilities feels like a wasted opportunity.

All the ports are situated at the rear of the cabinet towards the bottom and face downwards. That doesn’t make them too easy to reach, but given that there aren’t that many of them it’s not a big issue.

Asus ROG Strix XG27UCS review: How good is the image quality?

The first thing that strikes you about the XG27UCS is the clarity of the display. That’s really no surprise given that a 27in panel with a 3,840 x 2,160 display has a pixel density of 163ppi. That compares to 138ppi for the 32in LG UltraGear. No matter how hard you stare at the screen, you won’t be able to discern a hint of pixel structure.

Of course, that combination of 4K and 27in does make everything very small. If you value your eyesight, your first order of business will be to increase the display’s scale to 200%.

Pointing a colorimeter at the XG27UCS returned several results higher than the manufacturer’s claims. Gamut volumes are robust at 142.2% sRGB, 100.7% DCI-P3 and 97.9% Adobe RGB. Maximum brightness in SDR mode is 462cd/m2, rising to 526cd/m2 in HDR mode, the latter more than enough to justify the XG27UCS’s VESA DisplayHDR 400 rating.

The XG27UCS has an sRGB lock among the usual colour gaming modes. Using this, I measured the panel’s Delta E colour accuracy at 1.95. Selecting Cinema mode and measuring against the DCI-P3 profile resulted in a Delta E of 2.5. Given that scores between 1 and 2 mean colour variances are only perceptible to the trained eye with close scrutiny, both scores are satisfactory for a gaming monitor.

Panel uniformity was fine for a basic backlit IPS display, with only a few swatches falling into the nominal rather than recommended luminescence category. The ISO 14861 readings were a little more wayward but no worse than those of other comparable IPS gaming displays I’ve encountered recently.

The only slight fly in the ointment is the screen’s black luminescence, which, at 0.5cd/m2, is a little on the high side and results in a less-than-stellar contrast ratio of 868:1. Of course, if absolute zero black levels and infinite contrast are what you yearn for you’ll need to pay rather more for an OLED display. 

On the HDR front, the new Asus ROG does well for an IPS panel, just not spectacularly well. Putting some monitors into HDR mode can make a right dog’s dinner of the Windows desktop colour balance, but the XG27UCS coped well, so you can happily leave your PC in HDR mode if that’s your gaming preference.

If you want to adjust the colour settings manually, the XG27UCS has plenty of options. You can adjust the daylight colour temperature using seven presets, though at the 6,500K preset, the panel actually registered a rather warm 5,853K, overall saturation and six-axis saturation between 0 and 100 and the gamma between 1.8 and 2.6. Out of the box the gamma was set to 2.39 which worked for me.

Basic motion handling is very good. Running in standard mode with the 20-level overdrive set to zero, there was hardly any ghosting or smearing. Crank the OD up to 12 – the highest you can go without inverse ghosting creeping into the proceedings – and things look even better. On this front, the XG27UCS is almost OLED-like in its clarity.

The XG27UCS also features Asus ROG’s in-house backlight strobe technology, called ELMB or Extreme Low Motion Blur, to reduce motion blur. Much like the PureXP system found on ViewSonic monitors like the Omni XG2431, it works by turning off the monitor’s backlight between refreshes.

ELMB works wonders for motion fidelity, giving a truly OLED-like absence of blurring and ghosting. Still, it has some drawbacks: to engage it fully, you need to forgo adaptive sync, HDR and brightness adjustment. There are five clarity levels and these can be set to focus most strongly on the upper, lower or middle part of the display. I found Level 4 and middle to be the best options; Level 5 strength introduced a lot of overshoot.

Asus also offers a version of ELMB called ELMB-SYNC, which works with variable refresh rates, so you can run it along with G-Sync adaptive synchronisation. The problem with ELMB-SYNC is that it greatly reduces the maximum brightness. In testing, the brightness dropped to a stygian 27cd/m2 with ELMB-SYNC engaged.

After a week with the XG27UCS, I tended to use ELMB in its purest form for esports, where motion fidelity was most needed at the expense of adaptive sync because my GPU could easily sustain the fixed refresh rate that the system requires. I turned it off for more demanding AAA games like Senua’s Saga: Hellblade II to get the full benefit of G-Sync. In my opinion, the difference in motion quality between ELMB-SYNC on and off wasn’t enough to justify the massive drop in brightness.

READ NEXT: Best PC speakers

Asus ROG Strix XG27UCS review: Are there any other features I should know about?

As you’d expect from a thoroughbred gaming monitor, the XG27UCS comes with various usual bells and whistles. These are grouped into the GamePlus menu and include a big red stylised on-screen frame counter that can be set to show a simple number or a bar graph. You will need to download the Asus Display Widget CP to move the graphic’s on-screen location, however.

GamePlus also includes a crosshair, timer, stopwatch and display alignment functions. Asus now describes the dynamic crosshair and the shadow boost function as “AI” functions.

The GameVisual menu, meanwhile, houses nine different colour settings, including a Night Vision mode if you fancy playing your games through an ersatz green night sight. I spent most of my time in Cinema mode, which added a little more colour and contrast to my games, though your preference may differ.

Like many Asus ROG gaming displays, the XG27UCS lacks speakers. The reasoning behind this is sound; speakers would make the cabinet bigger and the price higher, and they would probably produce a sound that compares badly to a pair of good desktop speakers. In this day and age, an optical audio output wouldn’t have gone amiss.

Asus ROG Strix XG27UCS review: Should I buy it?

The XG27UCS is a compelling proposition. The limited connectivity options may be an issue for some—the lack of a KVM implementation does strike me as rather spoiling the ship for a ha’p’orth of tar—but the excellent levels of motion fidelity and the supreme clarity of the 4K panel more than make up for that.

Add the wide colour gamuts, compact design, highly adjustable stand and intuitive on-screen display into the bargain, and this is the most easily recommendable 4K gaming monitor on the market today, pipping the LG UltraGear 32GR93U thanks to its faster refresh speed and high DPI count.