Acer Predator X27 review: The Nvidia G-Sync HDR monitor that only lets you see half the fun

On paper, the Acer Predator X27 should be the bestest best gaming monitor to end all gaming monitors. It's got the same lovely 4K 144Hz IPS Nvidia G-Sync HDR panel with 384 dynamic backlight zones and 1000cd/m2 peak brightness as the Asus ROG Swift PG27UQ, but in the UK it costs £200 less than its Asus rival. That might not be of much consolation to anyone in the US, where both G-Sync HDR monitors cost a hoofing identical $2000 apiece, but when you're asked to choose between spending £2300 and £2100 for exactly the same panel (and I mean exactly the same), I know which one I'd rather choose - especially when the latter doesn't bombard you with an LED light show packed into its stand.

There is, however, a small problem (all right, a few small problems). For starters, it still costs $2000 / £2100. As I said in my Asus PG27UQ review, I could probably justify spending a grand on a fancy monitor like this (just) - I would definitely spend as much on a fancy Ultra HD Premium TV with HDR and 1000cd/m2 brightness - but more than double that? On yer bike, mate. Even if I did have that amount of money, though, I just couldn't get the Predator X27 to do HDR levels of brightness and HDR levels of colour, which absolutely isn't what you want from a two grand+ monitor. Here's how I got on.

I will preface this by saying the Predator X27 is still a very, very nice monitor. While I probably prefer the straight lines and slightly thicker stand of the Asus PG27UQ, the equally flexible and height-adjustable Predator X27 is definitely the least obnoxious of the two. There's a sprinkling of LEDs both at the back of the monitor and across the lower bezel, giving your desk a kind of blue underglow like one of those decked out motors off Pimp My Ride, but at least it's better than having the ROG logo splattered across your desk and ceiling. You can, of course, turn both sets of LEDs off using the onboard menu, but I quickly became quite fond of the X27's chilled-out mood lighting and ended up leaving it on.

I would also say the copious fans crammed into the back of the X27 (probably to prevent its G-Sync HDR gubbins from melting the panel in front of it) are perhaps a tad easier on the ears than the PG27UQ, but there's really not much in it. If anything, they're actually worse than the PG27UQ's fans, as they never actually switch off. Ever. If you're planning on putting this screen in a room where you sleep or do anything where the sweet sound of blower fans won't drive to you to distraction, you're going to have to unplug this thing from the wall even when it's turned off and you're not using it, because this thing never shuts up.

Noise issues aside, the X27 can be a real treat. Or at least it is if you remember to turn off the helpfully-named and definitely not at all confusing 'SDR Colours sRGB' option in the menu, as disabling this is what allows the monitor to display, quite literally, the full gamut of lovely HDR (or high dynamic range) level colour.

The difference is pretty astonishing, too. For example, when I tested the monitor using its User colour profie (which it automatically switches over to the moment you make any kind of alterations to its Standard, Movie or Eco modes) with SDR Colours sRGB in its default on position, my X-Rite i1 DisplayPro calibrator showed the X27 was only capable of displaying 96.2% of the regular sRGB colour gamut, 67.1% of the considerably larger and professional-grade Adobe RGB gamut and 69.0% of the all-important DCI-P3 gamut, which is the current standard for all HDR-enabled devices (see my What is HDR explainer for more info).

That's pretty decent for a regular IPS screen, but not exactly a ringing endorsement for a monitor that's threatening to eat your entire bank balance in a single sitting.

Thankfully, switching the SDR Colours sRGB option off improved the X27's colour accuracy immeasurably, which rather raises the question why this options is even there in the first place. With this turned off, the X27's sRGB coverage shot up to a perfect 100%, its Adobe RGB leapt to a very impressive 99.3%, and its DCI-P3 coverage hit a very lovely 93.0%. That's infinitely better, you may remember, than the underwhelming 69% DCI-P3 coverage I recorded for the PG27UQ, and I thought, 'Brilliant, this is exactly what I was hoping to see from a two grand gaming display.'

In the PG27UQ's defence, I've since been told there was, in fact, a very similar setting hidden somewhere in the depths of Asus' onboard menu system that supposedly did a very similar thing to SDR Colour sRGB option on the X27, which is probably why the colour accuracy results I got for that one were so much lower. I only got told about this after the monitor had been whisked away somewhere else, however, and I've yet to get one back in to retest it. Needless to say, though, it absolutely boggles the mind that both monitors effectively come crippled straight out of the box in regards to colour accuracy, and that neither of them have sufficiently clear menu settings to help rectify their initially lacklustre gamuts.

Alas, the euphoria of suddenly greener greens, redder reds and bluer blues didn't last long at all. For as soon as I turned on HDR in Windows 10, those lush, vibrant colours I'd just clapped eyes on in all of my test images effectively when straight back to what they looked like when SDR Colours sRGB was turned on. Its sRGB gamut coverage came in at 96.6% again, Adobe RGB at 68.3% and DCI-P3 a mediocre 70.6%.

Now, admittedly, my testing software doesn't produce its own HDR metadata, so the monitor wouldn't recognise my test patterns as proper HDR content anyway. As such, these particular tests will never be a completely accurate representation of what the monitor can actually do.

HDR games, on the other hand, do have their own HDR metadata, and I was hoping against all hope that this shift in vibrancy and muting of colours on my desktop and test images might just be a weird quirk to do the way HDR is implemented on Windows 10 (which, let's face it, is still a total mess despite its recent improvements).

Sadly, this wasn't the case at all. Don't get me wrong. Watching a proper 1000cd/m2 (if not closer to 1100-1200cd/m2, according to my calibrator) strength sunrise peak over the mountaintops of Assassin's Creed Odyssey is absolutely stunning. The sheer intensity of the light and its juxtaposition against the game's dimmer, pre-dawn surroundings (aided in no small part by the monitor's outstanding contrast ratio of 5962:1, excellent black level of 0.09cd/m2 and wider, sustained brightness of around 600-700cd/m2) is just spectacular. This is the stuff HDR is made for, and where it literally and figuratively shines the brightest.

The problem is that I couldn't get the monitor's HDR-level brightness working with its HDR-level colours.

I tried every possible combination of settings in the X27's menu system, fiddled endlessly with the Assassin's Creed Odyssey's own HDR settings, and still nothing managed to reproduce those same intense colours I saw with HDR switched off. Whatever the X27 is technically capable of achieving, it sure doesn't look like it according to my own eyeballs.

Take that image of the Odyssey sunrise again. In HDR, imagine a light blazing away in the sky, casting a neutral, but distinctively golden hue across the trees and hedges surrounding you. It's a lovely image and one you'd probably be perfectly happy with if you didn't know any better. Switch HDR off, however, and that same scene becomes transformed. That golden light is replaced by the vivid red of an early dawn with neighbouring clouds blushing pink, orange and mauve as the sun rises higher into the sky. Yes, you've lost some of the eye-searing brightness and sense of contrast, but man alive this is how I want my games to look, not the other way around.

Even smaller details like the red of Kassandra's mantle and the blue of the Grecian sky were richer with HDR turned off, making for a more pleasing image overall. With it on, Kassandra's hench outfit just looked a tad muted and a bit plain, while the sky didn't look like anything special at all. If it's even possible to describe another colour as being 'beige', it would be that.

It's immensely frustrating, as it's clear the monitor is perfectly capable of displaying almost the full DCI-P3 colour gamut. I know so because my calibrator said so. Yet something inside it is clearly preventing it from doing so when HDR is enabled.

To make sure it wasn't just a rare bad implementation on Ubisoft's part (no offence, Ubi), I went through the same process with Final Fantasy XV and Forza Horizon 4 as well. Sadly, my suspicions were confirmed here too. Colours looked beautiful in non-HDR, but a bit 'meh' in HDR. Forza Horizon 4 was, admittedly, the least disappointing of the lot - because gee whiz my heart did a little flip flop when I saw that autumn sun burst across the British countryside in the game's opening sequence - but there was still an appreciable difference in its overall colour vibrancy.

It essentially led to a situation where I had to pick between gorgeous, vivid colours and gorgeous brightness. For the sake of my eyes and general personal taste, I ended up choosing the colours every time.

It doesn't help that almost all of the Predator X27's picture settings are greyed out when HDR is enabled, giving you very few options to try and rectify it. The usual, adjustable Brightness setting suddenly becomes a locked down setting called Ref White whose number seemed to differ every time I opened the menu, came out of playing a game or simply turned the monitor on, while Contrast, Dark Boost, Auto Brightness and SDR Colours sRGB also become unalterable.

About the only thing of use you can actually change is the colour temperature, which I'd already set correctly using its customisable User setting when I calibrated it the first time (pumping Red and Blue up to 100 while dropping Green down to 90).

It's a stark contrast from what I remember the Asus ROG Swift PG27UQ looking like with HDR games onscreen (underwhelming measurements aside), but unless I get them both sat on my desk side by side it's difficult to say definitively which one actually does HDR better. Technically, they should both be able to do it as well as the other - they do, after all, share the exact same panel from the same manufacturer. In practice, however, I would cautiously put my bet on the Asus PG27UQ instead of the X27 - which is damn annoying when it costs £200 more.

Hopefully, it won't be too long before the PG27UQ wings its way back to me. Until then, however, I'd say hold your horses, because as far as I can tell, the Acer Predator X27 isn't the miracle monitor I wanted it to be.