LG 27G850A-B  Monitor Review

The LG 27G850A-B has a rather simple yet gamer-oriented design. It has a gray body and some branding in the back. The body is mainly plastic, and the base of the stand is metal. It also has some RGB lighting to complement your gaming setup.

The build quality is excellent. It's well-made with good-quality materials. The housing is plastic, which doesn't easily smudge, and the back only flexes a bit when you put pressure on it. There's no audible coil whine or fan noise either. The stand also holds the screen well without any noticeable wobble.

The ergonomics are great. You can adjust it in a number of ways, which feel smooth and easy to make. That said, you may find that the height at its lowest setting can be a bit high, as there's 3.8 inches (9.7 cm) of space between the desk and the bottom bezel. On the plus side, the stand holds the screen well, and it quickly stabilizes from any wobble. There's also a cutout for cable management.

The metal base of the stand takes up some space, but because it's flat, you can still put objects on top of it.

The weight measurement doesn't include the plastic casing for the inputs, which weighs 0.1 lbs (46 g).

There's a joystick on the back of the monitor to control the on-screen display and turn it on and off. The Dual-Mode button is also underneath the bottom bezel.

• DisplayPort cable (not DP 2.1 certified)
• HDMI cable
• USB-A to USB-B cable
• Power cable and brick
• User guides
• Mouse bungee clip

The LG 27G850A-B has an okay contrast ratio. With an IPS Black panel, it displays deeper blacks in dark rooms than normal IPS displays, but they still look gray against bright highlights. Unfortunately, its local dimming feature fails to further improve it.

Settings

• Deep Black Pro: High

The local dimming feature performs badly. It's edge-lit, with only eight vertical zones that limit its performance and effectiveness. With real content, the feature does improve the black levels compared to when it's off, especially in dark scenes. It keeps details well, but any large, bright object causes the center zones to light up, resulting in haloing. This applies to subtitles as well, although it's not overly distracting either. It looks good for an edge-lit local dimming feature, but it's slow to keep up with objects moving quickly between zones as it generally takes time for a zone to turn off.

The biggest downside with this feature, though, is how it causes big changes in brightness between different scenes or content, otherwise known as Automatic Brightness Limiting (ABL). This can get distracting during general desktop use, like when you're minimizing and maximizing windows. It also dims small, bright highlights on a dark background, so they don't pop. This happens with any of the Deep Black Pro settings, but 'High' and 'Middle' have the most aggressive ABL. 'Low' is less aggressive, but the screen is dimmer, and the zones don't turn off as much.

Settings

• Game Mode: Gamer 1 (after calibration)
• Brightness: 100
• Deep Black Pro: Off
• Smart Energy Saving: Off

The SDR brightness is great. It gets bright enough to fight glare in most well-lit rooms, but visibility can still be a problem in sunny rooms. However, it's the brightest if you don't use local dimming, and using it results in an aggressive ABL, which you might find distracting when minimizing and maximizing windows. You can see the results with the various Deep Black Pro settings below:

Settings

• Game Mode: Gamer 1 (after calibration)
• Brightness: 100
• Deep Black Pro: Off
• Smart Energy Saving: Off

The HDR brightness is excellent. It gets very bright, and you won't have many issues using it in a well-lit room, but it doesn't make small highlights pop against the rest of the image. It doesn't have the best PQ EOTF tracking either, as it displays most content brighter than what the creator intended. At least it has a sharp cut-off at the peak brightness, letting highlights get as bright as possible, at the cost of losing details.

Using the local dimming feature actually dims the screen and mutes small highlights, as you can see with the various Deep Black Pro settings below. The PQ EOTF also has a slower roll-off with local dimming enabled, so the monitor preserves more details, but doesn't let all highlights get the brightest they could.

The horizontal viewing angle is decent. Although the image gets darker at wide angles, it's still fine to share your screen with someone sitting right next to you.

The LG 27G850A-B has an okay vertical viewing angle. The screen washes out and looks darker from wide angles, but you still see a consistent image if you're standing up and looking down at the screen.

The gray uniformity is good. Although the edges are darker than the rest of the screen, it has minimal dirty screen effect in the center, which is good for web browsing or work. You can also see the 5% gray uniformity.

The black uniformity isn't bad. There's clouding and backlight bleed without local dimming. Enabling the local dimming feature improves the uniformity, and looks best with Deep Black Pro on 'High,' which is what the results are with. It looks similar with Deep Black Pro on 'Middle' and 'Low,' though.

The accuracy before calibration in the 'sRGB' Game Mode is very good. It locks colors well to the sRGB color space, but there are still some inaccuracies. The white balance is off with any shade of gray, and the color temperature is on the cold side. The gamma tracking is off, with most scenes looking too dark.

Using the 'sRGB' Game Mode locks a few settings, including:

• Black Stabilizer
• Response Time
• Sharpness
• Gamma
• Color Temp
• Six Color
• Black Level
• Smart Energy Saving

You'd have to use another, less-accurate picture mode with oversaturated colors if you want access to these settings.

The accuracy after calibration is superb. Calibrating it fixes most issues, as any remaining inaccuracies with the white balance and gamma are hard to spot.

The SDR color gamut is remarkable. It displays a wide range of colors in the sRGB and Adobe RGB color spaces. While colors are oversaturated and inaccurate in Adobe RGB, you may be able to fix that with a color-managed app.

The LG 27G850A has an incredible HDR color gamut. It displays nearly all colors in the DCI-P3 color space, with only minor inaccuracies. It also displays a wide range of colors in the Rec. 2020 color space, but colors like green and cyan are undersaturated.

The HDR color volume is great. It displays most colors well, but doesn't properly display dark and very bright colors. These results are with Deep Black Pro off, as enabling it worsens the color volume because the screen is dimmer with it on.

The text clarity is fantastic when using a 4k resolution. Text looks sharp and is easy to read. However, it looks worse when using the 'On (Full Wide)' and 'On (24")' Dual-Modes, which use a 1080p resolution. Scaling, in particular, looks bad with the 24-inch mode. You can see more text clarity photos with the different Dual-Mode settings and various operating systems and settings below:

The direct reflection handling is good. Although the matte coating spreads light out, it still has some mirror-like reflections that could get distracting in a bright room.

The LG UltraGear 27G850A-B does a fantastic job at maintaining consistent black levels in a bright room. However, because it doesn't have a high contrast ratio, blacks still look gray in a bright room.

The LG 27G850A has a lot of reflected light coming off the screen in a bright room. This can make visibility an issue, especially if you have it placed opposite a sunny window.

The gradient handling is fantastic. There's minimal banding between shades of similar colors, but it still has some in darker shades.

The max refresh rate depends on the Dual-Mode setting you're using. With it off, you can get a 4k @ 240Hz signal over HDMI or DisplayPort with Display Stream Compression (DSC). With Dual-Mode set to 'On (Full wide)' or 'On (24")', you get a 1080p @ 480Hz signal without any DSC over HDMI or DisplayPort.

The LG UltraGear 27G850A-B also supports HDMI Forum VRR.

The LG 27G850A-B has decent motion handling across its VRR range. The 'Fast' Response Time setting performs consistently the best at high refresh rates, but it has inverse ghosting at low refresh rates, so you may prefer using 'Normal' if that bothers you. For the most part, motion looks the same with the 'Fast' overdrive setting, no matter which Dual-Mode setting you're using, which is why we didn't include pursuit photos for frame rates of 240 fps and below with Dual-Mode on. The only exception is that Low Framerate Compensation (LFC) activates earlier with Dual-Mode on than with it off, so when the frame rate reaches 60 fps, the screen is actually refreshing at 120Hz. This means that, with Dual-Mode on, motion looks the same at 60Hz as at 120Hz.

The refresh rate compliance is decent. The monitor makes most full-color transitions at low frame rates, but it struggles a lot more at high frame rates, like if you're using its 480Hz Dual-Mode. These results are with Dual-Mode off, but they're similar in the Dual-Mode at the same frame rates.

The CAD at 240Hz with Dual-Mode off is good. Motion looks sharp for the most part, but there's still blur with fast-moving objects. The 'Fast' Response Time setting performs the best, as there's less blur than 'Off' and 'Normal,' and it has less inverse ghosting than 'Faster.' 

If you're using the Dual-Mode feature at the max refresh rate of 480Hz, 'Faster' has the best motion, although it has some inverse ghosting. That said, the overdrive settings perform the same at 240Hz as with Dual-Mode off.

The CAD at 120Hz is decent, and it performs similarly no matter the Dual-Mode you're using. Unlike at its max refresh rate, the 'Normal' Response Time setting performs the best, as 'Fast' and 'Faster' have too much inverse ghosting. That said, 'Normal' still has blur with fast-moving objects.

The CAD at 60Hz is okay. It's the same with Dual-Mode on or off because using a fixed 60Hz signal doesn't activate LFC like if the refresh rate would drop down to 60Hz from a higher refresh rate rate. The 'Normal' Response Time setting performs the best, but it has more inverse ghosting than 'Off,' which is better to use if that bothers you, although it has more blur.

The LG 27G850A doesn't have a backlight strobing feature to reduce persistence blur.

There's minimal VRR flicker with changing frame rates on the LG 27G850A. While it has some flicker with the Dual-Mode off in dark scenes, it isn't distracting. That said, there's a bit more flicker when using the 480Hz Dual-Mode due to the larger refresh rate range. You can see the results below:

The LG UltraGear 27G850A-B doesn't use pulse-width modulation and the backlight is flicker-free.

The LG 27G850A-B has low input lag for a responsive feel no matter the refresh rate you're gaming at. It's marginally different when using the Dual-Mode at 60Hz and 120Hz:

The resolution changes to 1920x1080 when using either of the Dual-Mode settings.

The LG 27G850A supports any signal with a PS5 or PS5 Pro, as long as you have Dual-Mode off.

Besides the fact that you need to enable HDMI override on the console to get 1440p @ 60Hz, this monitor works well with an Xbox Series X|S. The console doesn't support HDR with 1080p and 1440p, so this isn't a limitation of the monitor.

Tested with: M2 MacBook Pro (Sequoia 15.5) and M4 Max MacBook Pro

The LG 27G850A works well with macOS. Over HDMI, the 'Gamer 1' and 'Personalized Picture' Game Modes in HDR look closest to a MacBook display, and there aren't any issues. If you're using a USB-C to DisplayPort connection with Dual-Mode on, you need to enable VRR to get HDR. The 'RTS' and 'Personalized Picture' Game Modes are the closest to a MacBook display's picture quality in HDR.

Regardless of the connection you're using, if you're using a MacBook with it plugged into power and you close the lid, you can continue working on the monitor. However, if the MacBook isn't plugged into power and you close the lid, the monitor goes to sleep. Windows return to their original position when reopening the lid, or waking the laptop up from sleep.

The LG UltraGear 27G850A-B has as a few extra features, including:

• Black Stabilizer: Changes the black level so that it's easier to see opponents in dark scenes.
• Crosshair: Adds a virtual crosshair that your system's anti-cheat tool won't detect.
• Dual-Mode: Allows you to change the resolution to 1080p and refresh rate to 480Hz. There's also an option to simulate a 24-inch screen size in the 1080p Dual-Mode.
• FPS Counter: Shows the current frame rate from your source.
• Hexagon Lighting: Allows you to customize the RGB lighting on the back of the monitor.
• LG Switch: This is a downloadable program that lets you split the display into different sections.

You can learn more about the OSD with the user manual.