LG 27UP850 Ultrafine 4K IPS Monitor Review

If you are after a stunning 4K IPS monitor for work and maybe even a bit of gaming, LG’s 27UP850 might stand out as one of the best options available. With a gorgeous 4K IPS panel pushing 400 nits of peak SDR brightness, a quoted 95% coverage of the DCI P3 spectrum and a quoted 5ms GtG response time, it sure seems like a great choice. Luckily, I can test all those claims and more so let’s take a look. Visually I think it looks great. Styling wise they’ve gone for a very minimal aesthetic as always and I think it works really well. The stand looks good, but feels incredibly cheap. You do get a little bit of adjustability – just tilt and height adjust but that’s enough for most. The only annoying thing is the power button and menu joystick on the bottom. It works fine, the menu is easy enough to navigate, but it has a pretty bright white LED behind it, which when your system is switched off will flash on and off. If you keep this in, say, your bedroom I could see that being annoying.

As for the panel, to the eye it looks great. 4K at just 27” offers an incredible pixel density and brilliant sharpness you’ll struggle to find elsewhere. When watching 4K content it stands out as a visually beautiful picture. The colours are vibrant and rich, while of course retaining the sharpness and details well. To quantify that though I’ll crack out my SpyderX. It recorded 97% coverage of the DCI P3 spectrum, actually beating the 95% quoted figure. That’s excellent, especially since this isn’t exactly a reference display. Even better news is that it also beats its brightness figure, hitting 413 nits in my testing, or as high as 436 nits from LG’s calibration software. Interestingly, after calibrating the display it actually increased to 431 nits in datacolor’s test. Sadly the contrast ratio isn’t quite as good as they claim – they say the typical is 1200:1 whereas I only got 1060:1 – although they do say that 1000:1 is the minimum which this model does exceed and I should note that after calibrating at max brightness it got better at 1140:1. Still not quite 1200:1 but definitely better. That just means that the HDR experience is pretty naff as the blacks are more grey than black.

Speaking of their calibration software, it works with most colourimeters. It’ll work with the X-Rite ColorMunki, i1DISPLAY Pro, Pro Plus, Studio and i1Pro2 and i1Pro3, plus the Spyder5 and SypderX and even some higher end tools like the Klein K10A. I’ve got a SpyderX so I ran it with that, and the magic here is that the calibration profile is actually loaded onto the monitor as a picture mode, so unlike most displays where the calibration gets loaded into your video card to alter the image it outputs to then get accurate colours, this alters the monitor’s profile. Out of the box I measured a deltaE of just 2.5 which is just outside the target of under 2, with the darker shades being the most out of spec. Happily, after the calibration it’s practically perfect. It averaged just 0.74 deltaE, with no result exceeding the threshold of 2. Excellent.

One area I was surprised to find wasn’t quite as good was the panel uniformity. The lower right corner was considerably (although not visibly) dimmer than the brightest area in the centre. Like, 18% less light. The centre was at 408 nits, while the lower right was at just 335 nits! In fact, both the top and bottom edges were generally over 10% down from the centre. While I can’t say I noticed that in use, that’s less than ideal for sure.

When it comes to speed, this panel isn’t the best there either. Being a 60Hz panel it only needs to average below 16.67ms to not show any visible ghosting. Of course testing with my new OSRTT PRO model – available at osrtt.com, you’ll find with overdrive off, it doesn’t even come close. It averaged more like 20ms, with some of the slower results taking over 30ms. That’s painful. Happily with overdrive on its “Fast” setting you get much more reasonable results. The average comes down below the refresh rate to more like 14ms – which is still painfully slow mind you – but it’s as fast as you’ll get without much overshoot. If you do step it up to “Fastest”, as LG note on their 5ms GtG claim, the average only comes down to 10ms and you get some horrific overshoot. A quick peek at the UFO test at high speed confirms that the “Fast” mode is the best option.

As for input lag, the Time Sleuth reported just 2.1ms of on display latency, and I’m happy to report that my new input lag testing mode for the response time tool reports a decent 7.5ms for the on display latency. The discrepancy there is down to the refresh rate taking so long. The key thing to see here though is that none of the results took more than a single frame to start rendering which is great news.

So that means it should be great for gaming then, right? Well, no, not really. As far as 4K 60Hz monitors go, it’s just as good as the rest, but that isn’t saying too much. The slow refresh rate and response times mean motion feels sluggish and smeared. Even the perceived responsiveness – despite the relatively low latency results – was noticeably lacking compared to even a basic 144Hz 1440p monitor of the same size. It’s not intrinsically bad for gaming, it’s just not the most amazing experience. Still, as far as 4K 60Hz monitors go, this is definitely a good one.

For content consumption – hell even content creation – this is an excellent choice. The mix of good brightness which is enough for everything but direct sunlight, wide colour gamut coverage, built in calibrated profiles, and clean aesthetic makes it a pleasure to use. The colours look fantastic, whether it’s movies or massive emails, I think it’s a great shout. The only downside is the price, which as standard retails for £400. I have it on good authority though that when these are on sale, you can spend as little as £270 for one, and at that price it’s an absolute no-brainer. Besides the response time measurement, it’s pretty honest about all its specs, it looks great and even has all the inputs you’d want, including type C with 96W charging, DisplayPort 1.4 and two HDMI ports, and even a two port USB hub. It even has some built in speakers that – while still pretty naff – sound better than most monitor speakers I’ve tested. It really is a great deal, when it’s on offer. When it’s not.. I’m not quite as sure.