AOC Q27G3XMN Review – Budget MiniLED 1440p 180Hz Gaming Monitor

This is an astonishingly cheap 1440p 180Hz MiniLED gaming monitor. It retails for just £350, which would be on the cheaper end for being a 1440p high refresh rate gaming monitor anyway, let alone having a MiniLED backlight! This is the AOC Q27G3XMN, and this is a hopefully rather thorough review! Starting with the specs and claimed figures, AOC claims this bad boy has a “1ms GtG response time”, 1000 nits of peak brightness, a DeltaE of less than two and 98.5% coverage of the DCI P3 spectrum. As for inputs, we’ve got two HDMI 2.0 ports – no 2.1 here, which also means you can get 144Hz at most over HDMI – and one DisplayPort 1.4 port which can do the full 180 hertz this monitor is capable of. 

As for the physical, design wise this still follows AOC’s G2 and G3 line styling with a few red accents and an otherwise inoffensive design. There’s no RGB LEDs to be found, and annoyingly there’s no joystick style switch for the OSD either. Instead we have the cursed downward facing individual buttons. Interestingly, the OSD has actually been upgraded to AOC’s newer design – albeit in black and white and just as painful to navigate as the old design. Still, all the usual settings are there, including the four steps of overdrive we’ll be testing a little later, and for me the most interesting here is the local dimming setting. This drops the brightness quite a bit, and even more interestingly, this isn’t just an on/off setting, there are four levels including off. Essentially the highest mode is the full local dimming experience – everything is as black as it can be when there isn’t meant to be any light. The two other, less intense, settings basically just dim the backlight instead of turning it fully off. I guess this is, in theory anyway, meant to help blend the haloing in a little more, but in practice I don’t know why you’d opt for anything other than either off or maximum on. 

Since we’re already talking about the MiniLED backlight, I should mention the key detail that will put this budget beast into context. This has 336 backlight zones. For context, Apple’s MiniLED displays have 2,500 zones, and a 1440p OLED has 3.686 million zones – technically it’s actually 11 million since each sub-pixel has independent brightness control, but still you can see how just 336 zones over 27 inches of display makes for a less-than-ideal experience. Haloing is… really, really bad. On a black background – which I will admit is a worst case scenario – anything even remotely bright has the widest outer glow I’ve seen on a MiniLED display. This white bar has haloing twice its width on either side. What’s worse is that it flickers like crazy. Here’s that bar in motion… The camera doesn’t pick this up as well as your eyes would, but you can still see that flicker happening – now imagine that that’s 600 nits worth of flicker.. Yeah it’s not great. Personally I’d leave local dimming off on this thing and just enjoy the great brightness instead. 

Interestingly, it seems I can actually quantify that flickering. See, I ran my Open Source Response Time Tool – specifically my newest Pro CS model that you can pick up at OSRTT.com by the way – with local dimming on strong, and caught some rather strange behaviour. Here’s one of those graphs. The backlight turns on to half way between the two steps here, and actually stays there for THREE FRAMES, before then jumping a touch high and finally coming back down. Here’s another transition, this time a white-to-black one, and this is just all over the place! And here’s one more. Again, it takes three whole frames for it to actually turn the backlight on properly – and this isn’t even going from full black! This is from RGB 51! Anything from actual black to fully on and it’s instant, but anything where the backlight is already on but dim seems to take nearly 20 milliseconds to respond. It’s really weird, so again I’d leave local dimming off personally.

One thing I am happy to report is that AOC has drastically improved the frequency that the MiniLED backlight is controlled by. As a brief bit of context here, you generally have two options for how to control the brightness of an LED. Either lower the voltage going to it – that’s called DC control – or you can pulse the LED on and off for enough time to get the same result – that’s called PWM or pulse-width modulation. The latter is generally worse as that flicker can be uncomfortable, and outright bad for your eyes. The faster that flicker though, the less perceptible it is, and the less bad it becomes. The last AOC MiniLED monitor I tested, the AG274QXM, had a frequency of just 500 hertz, a completely unusable choice. Happily, this panel runs considerably faster. It’s well into the thousands of hertz – possibly tens of thousands – so it is much, much better. Great job AOC! 

I should talk about response times – with local dimming off anyway. With overdrive turned off, the panel actually isn’t too bad. It ran 5.7 milliseconds on average, which is only 175 hertz – meaning the native panel performance is exceptionally close to the maximum refresh rate. That’s great news! Overdrive on “Weak” drops the average to just 5.3 milliseconds which is under the 5.56 millisecond refresh rate window which is fantastic to see. My preferred overdrive mode by far though is “Medium”, which drops the average to an excellent 4.1 milliseconds, making for a sharp, responsive and smooth visual experience, with functionally no overshoot too. Lastly, we have the marketing mode – sorry “Strong” – where technically the initial response time average does drop to an excellent 2.4 milliseconds, but thanks to the horrible overshoot you’ll struggle to believe that, and the 5.4 millisecond perceived time average feels a lot more accurate. Don’t use this mode, use Medium. 

As for input lag, I’m happy to report that was spot on too, with very few results taking longer than one frame to display an input. That means the gaming experience, especially when coupled with the pretty fast response times, is great. It’s smooth enough to hit your targets, it’s quick enough to let you Han Solo your opponents, and all around it’s a great time. While this isn’t exactly an esports display, you certainly can play competitively on this – assuming you have the skill to back it up! I actually really like how games look on this – both in motion and the vibrancy. The MiniLED backlight really helps this ‘pop’.

It turns out that’s because you get 650 nits of peak brightness here, and even with local dimming disabled you still get an above-average 5560:1 contrast ratio. Of course with local dimming enabled you get an infinite contrast ratio –  although interestingly you do get less measured brightness at 585 nits instead of 650. This is also considerably less than the 1000 nits AOC claims, although I suspect that is in HDR on a small window size. The full-screen SDR brightness peak seems to be around 650 nits. As for colours, gamut coverage is great at 97% of the DCI P3 spectrum, or 76% of Rec2020, and accuracy is top notch with a DeltaE of 1.03 on average in my testing. It does actually come with a calibration report in the box too, so that’s pretty nice. In general content looks great on this, it’s vibrant, rich and more than bright enough for sure!

The Q27G3XMN is a glimpse into the future. MiniLED backlights being this accessibly cheap – just £350 here in the UK at the time of filming – is amazing. In fact, at £350 that makes this a pretty cheap 1440p 180Hz monitor outright, even forgetting the backlight, so I’d argue it’s worth considering just on that alone. The response times and latency figures make it a great gaming experience, and when you add in the vibrancy and brightness, it’s just a great shout. The local dimming, on the other hand, leaves a lot to be desired. With more zones – like 3000 instead of 300 – it might be a better experience, and if they can get rid of the flicker that’d be great too, but to me this is a peek into the future of LCD monitors. MiniLED backlights, to me, are a compromise compared to an OLED, but with enough backlight zones I think it keeps LCDs relevant until more OLED manufacturers are allowed to get into the business. If this is a sign of what’s to come, I’m excited. And that’s not to say this isn’t worth buying – it is, but not for the local dimming.