LG 27GN850-B Monitor Review

The LG 27GN850-B has the same style as most of LG's UltraGear monitors from their 2020 lineup, such as the LG 27GN950-B. It has thin borders on three sides with a thicker bottom bezel. It's mainly black with red accents throughout. Unlike the LG 27GL850-B, the V-shaped feet don't sit flat on the desk and are a bit elevated. There's cable management through the stand, and overall it's a fairly well-built monitor.

The wide stand supports the monitor well, and the feet are fairly thin, so there's enough space to put stuff in front.

Like most LG monitors, the ergonomics are disappointing. The tilt range is limited, and you can rotate the screen into portrait mode, but since you can only do it in the clockwise direction, the inputs would be on top. This could be an issue if you have short cables.

The back of the monitor has the same red ring found on most UltraGear monitors, but it doesn't light up. There's cable management through the hook in the stand.

The borders are thin and aren't distracting, which is great for a multi-monitor setup.

Update 06/01/2021: We mistakenly indicated the thickness with stand as 32.2 cm instead of 22.2 cm. It has been fixed.

The screen itself is very thin, but the whole setup gets thicker with the stand attached. You may need a deep desk to put it on.

The LG 27GN850-B's build quality is decent. It's similar to the LG 27GN950-B, and it's made entirely out of basic, plastic materials that feel solid. There aren't any obvious gaps or loose parts. The stand supports the screen well, and there isn't much wobble. However, the hook for cable management feels a bit flimsy, but this may only be a problem if you're constantly removing cables from it.

The LG 27GN850 has a low contrast ratio, which is expected from an IPS panel. Blacks appear gray when viewed in the dark, and there's no local dimming feature to help improve it. This is lower than the advertised 1000:1 contrast, but it may vary between units.

The LG 27GN850-B doesn't have a local dimming feature. The above video is provided for reference only.

The LG 27GN850-B has good SDR peak brightness. It maintains its brightness extremely consistent across different content, and it gets bright enough to combat glare. However, this is lower than the advertised 350 cd/m². We measured peak brightness after calibration in the 'Gamer 1' Picture Mode with Brightness set to max.

The LG 27GN850 has mediocre HDR peak brightness. It only gets a bit brighter than in SDR, and highlights quickly lose their brightness the longer they stay on the screen. It's not enough to make highlights pop the way the creator intended in HDR. We measured the HDR peak brightness in the 'Gamer 2' Picture Mode.

The LG 27GN850 has an excellent horizontal viewing angle, which is normal for an IPS panel. The image remains accurate as you move off-center, which is great if you want to use it for co-op gaming.

The vertical viewing angle isn't bad. You may notice a loss in image accuracy if you mount the monitor above eye level.

Our unit of the LG 27GN850 has excellent gray uniformity, but this may vary between units. The edges of the screen are a bit darker, but there's no dirty screen effect in the center. Solid colors across the screen, like on a web page or document, look great. Uniformity is even better in near-dark scenes.

Black uniformity is poor, but this may vary between units. There's noticeable backlight bleed in the corners and clouding throughout. This could be distracting when watching dark scenes in a dark environment.

The LG UltraGear 27GN850-B has good out-of-the-box accuracy. White balance is only a bit off, and most colors are slightly inaccurate. The color temperature is a bit on the cold side, giving the image a blueish tint. Sadly, gamma doesn't follow the target curve at all, and most scenes are brighter than they should be.

There's an 'sRGB' Picture Mode, but we didn't use it because it resulted in a less accurate image:

• Color Temperature: 6484K.
• White Balance dE: 4.51.
• Color dE: 2.84.

The LG 27GN850 has remarkable accuracy after calibration. Any remaining inaccuracies with white balance and most colors can't be spotted by the naked eye. Gamma follows the target curve very well, and the color temperature is extremely close to the 6500K target.

You can download our ICC profile calibration here. This is provided for reference only and shouldn't be used, as the calibration values vary per individual unit even for the same model due to manufacturing tolerances.

The SDR color gamut is incredible. It has full coverage of the sRGB color space used in most web content, and excellent coverage of the Adobe RGB color space, which is great for photo editors.

The LG 27GN850-B's color volume is fantastic. Helped by its incredible color gamut and good peak brightness, it displays colors at a wide range of luminance levels. However, it can't display deep colors due to the low contrast ratio.

The LG 27GN850-B has a good HDR color gamut, and it's an improvement from the LG 27GL850-B. It has great coverage of the commonly-used DCI P3 color space and decent coverage of the wider Rec. 2020.

The DCI P3 coverage is much lower than the advertised 98% coverage. This is normal and is due to the way we measure DCI P3. We measure DCI P3 by sending a Rec. 2020 signal, but unlike most reviewers, we limit the colors we're sending to the DCI P3 primaries. This results in a lower, but arguably more accurate measurement.

The HDR color volume is decent. Aided by its good color gamut, it displays a wide range of colors but struggles with darker colors because it has a low contrast ratio.

There are no signs of temporary image retention on our unit of the LG UltraGear 27GN850, but this may vary between units.

The gradient handling is exceptional. There's virtually no banding with any shade.

There's some extremely minor vertical color bleed, but it shouldn't be noticeable with most content.

The LG UltraGear 27GN850-B's reflection handling is decent, similar to the LG 34GN850-B. It performs well in moderately-lit rooms, but the reflections may be too distracting if there's direct sunlight on it.

The LG 27GN850's text clarity is decent. Enabling ClearType (top photo) helps improve the appearance of diagonal lines, such as on R, N, G, and S, but straight lines aren't as bold, as seen on the letters T and I.

The response time at its max refresh rate of 144Hz is incredible. The recommended overdrive setting is 'Normal' as it results in crisp motion and minimal blur with almost no overshoot. The 'Fast' and 'Faster' settings result in too much overshoot and motion blur.

The LG 27GN850's response time at 60Hz is outstanding. Like at its max refresh rate, the 'Normal' overdrive setting results in a lot less overshoot than the 'Fast' and 'Faster' settings, and motion looks buttery smooth. This means that you won't have to change the overdrive setting if the frame rate of your game drops.

The LG 27GN850-B has a flicker-free backlight, which helps reduce eye strain.

Unfortunately, the LG UltraGear 27GN850-B doesn't have an optional black frame insertion feature to help reduce motion blur. The replacement model, the LG 27GP850-B, has a BFI feature, but it's only available between a narrow range of refresh rates, and it can't be used at the same time as FreeSync.

Update 05/06/2021: We've changed the FreeSync support from 'Native' to 'Compatible' for consistency.

The LG 27GN850 has an outstanding 144Hz refresh rate. It has native Adaptive Sync support, meaning it supports both FreeSync and is G-SYNC compatible as well. Both FreeSync and G-SYNC work over a DisplayPort connection at its full range, and over HDMI, only FreeSync works between 20-100Hz. If you prefer something with a higher 165Hz refresh rate, then check out the MSI Optix MAG274QRF-QD.

The input lag of the LG 27GN850-B is incredibly low. It increases a bit at 60Hz, but it shouldn't be an issue for most people. We weren't able to measure the 10-bit HDR input lag because we can only achieve its full 144Hz refresh rate over a DisplayPort connection, and we don't have the tools necessary to measure the HDR input lag over DP. The max 10-bit refresh rate over HDMI is 60Hz. That said, we don't expect the input lag to significantly increase in HDR.

The LG 27GN850 has a great resolution and size. There's enough space to open multiple windows side-by-side, and the 1440p resolution helps deliver crisp images.

The LG 27GN850-B has a few extra features, such as:

• Crosshair: allows you to add a virtual crosshair for FPS games.
• Black Stabilizer: Adjusts the gamma in dark games, so you can see your opponents in the shadows better.
• Low Blue Light: Removes blue light to help reduce eye strain.

There's a single joystick underneath the bottom bezel to control the on-screen menu.

• DisplayPort cable
• HDMI cable
• Power cable and brick
• Manual and drivers