LG has finally leaped forward by introducing its first 27-inch 240Hz gaming monitor, featuring the classic 4K IPS panel format with a 16:9 aspect ratio. Not OLED, not IPS with Mini-LED, but a regular Edge-LED IPS. But not a simple one, but an advanced one, with a bunch of the latest developments and improvements at the hardware level. The recently introduced new LG 27G850A-B from the well-known UltraGear gaming line has a slightly confusing name that directly echoes the manufacturer’s trendy WQHD solutions, but this is an entirely different display, a class higher. Let’s get to know it better in this LG 27G850A-B review.
LG 27G850A-B Specifications
- Display: 27-inch Nano IPS Panel, Anti-glare
- Resolution: 3840 x 2160 (4K UHD 240Hz) / 1920 x 1080 (FHD 480Hz)
- Aspect Ratio: 16:9
- Brightness: 450 cd/m² (Typ) / 360 cd/m² (Min)
- Color Depth: 1.07 Billion
- Color Gamut: DCI-P3 99% (CIE1976)
- Contrast Ratio: 2000:1 (Typ.) / 1400:1 (Min.)
- Pixel Pitch: 0.1554 x 0.1554
- PPI: 163 PPI
- Refresh Rate: 240Hz
- Response Time: 1 ms (GTG)
- Viewing Angle: 178˚(R/L), 178˚(U/D)
- Features: Dual Mode Refresh Rate, Unity Hexagon Lighting, AMD FreeSYnc Premium Pro, NVIDIA G-Sync Compatible, DTS Headphone:X, VESA Adaptive Sync, Dual Mode, LG Switch, Auto Input Switch, Black Stabilizer, Color Calibrated, Color Weakness Mode, Crosshair, Dual Controller, Dynamic Action Sync, Factory Calibration, Flicker Safe, FPS Counter, H/W Calibration (True Color Pro), HDR Effect, HDR10, Live Color Low Blue Light, Reader Mode, Smart Energy Saving, True Color Pro, User Define Key, VESA DisplayHDR 600, VESA DSC
- Ports: 2 x HDMI 2.1, 1 x DisplayPort 2.1, 2 x USB 3.2 Gen 1, 1 x Headphone output, Headphone 4-Pole (Sound+Mic)
- Stand: Tilt (-8~15º), Swivel (-30~30º), Height Adj. (110 mm), Pivot
- Audio: Built-in Speaker
- VESA Mount: 100 x 100 mm
- Dimensions: 24.2″ x 22.9″ x 9.9″ (with stand)
- Weight: 20.7 lbs (with stand)
If you’re curious about unboxing the LG 27G850A-B and exploring its intricate design details, check out our dedicated hands-on article where I dive deep into those aspects. In this LG 27G850A-B review, I’ll skip the initial overview and design impressions to dive straight into the monitor’s menu system, settings, and performance. Feel free to visit the hands-on piece for a comprehensive look at its physical build and first impressions.
LG 27G850A-B Review
Menu and Control
The monitor is controlled by a five-position joystick located on the lower edge of the case in the central part. The control element itself is very convenient, practical, and familiar. The status indicator is not used in the new 27G850A-B.
The control system is convenient and requires no adjustment. Thanks to on-screen prompts, you can navigate the menu at any time of day without experiencing discomfort or problems.
Pressing the joystick brings up the familiar animated OSD menu with five icons.
Main Menu Access:
- Available via the dedicated on-screen control button
- Five main sections, with layout and content similar to other recent LG LCD monitors
1. Preset Modes / Picture Modes
- Allows quick selection of preset modes, most tailored for gaming
- Includes sRGB emulation mode
- Adjustable backlight brightness
- Full RGB color temperature control (great for wide-gamut displays)
- Two hardware calibration memory slots (Calibration 1 and 2) for use with LG’s calibration software
- Custom user preset for manual adjustments and saving personal preferences
2. Game Adjust
- Enables Adaptive-Sync, with the choice of advanced or standard mode
- Response Time/Overdrive adjustment for motion clarity
- Black Stabilizer for enhancing dark scene visibility
- Crosshair (sight) and refresh rate/FPS counter overlays
- Note: FPS counter shows refresh rate, not system performance
- Reset option for restoring gaming settings to default
- Some options may be unavailable or greyed out in specific modes; OSD prompts indicate incompatibilities
3. Picture Adjust
- Standard image controls:
- Brightness
- Contrast
- Gamma
- Color temperature with full RGB and 6-axis color adjustments
- HDMI “Black Level” control
- Deep Black Pro toggle
- Sharpness (generally best left at default)
- Reset option for image settings
4. Sound
- Equalizer presets for 3.5mm output
- Volume control for headphones/external speakers
5. Input
- Signal source selection (manual or automatic)
- Aspect ratio options: Full Wide, or Original
- Lacks features like PiP/PbP, KVM, and MST
6. General
- OSD language selection
- Two customizable quick access keys
- Automatic standby and Deep Sleep mode
- Smart Energy Saving (recommended to disable for stable backlighting)
- DisplayPort mode selection for compatibility
- Menu lock and sound effects toggle
- Built-in screen test utility for checking the display
- Reset all settings to factory defaults
- Info panel with operating hours counter
LG 27G850A-B review test
Color Gamut
The 27G850A-B 4K HDMI 2.1 gaming monitor features a new Nano IPS Black from LG Display, which includes a modified backlight spectrum and an expanded color gamut. Let’s check its capabilities using our LG 27G850A-B review product below:
We initially checked the display using its factory settings in Player 1 mode. The screenshots reveal that two of the three reference points shift noticeably in space compared to the standard sRGB color profile, exceeding it in several areas. Compared to the even wider DCI-P3, for which the manufacturer claims 99% compliance, the 240Hz IPS gaming monitor slightly surpasses it in a couple of areas. After manual adjustment and calibration, the monitor becomes a little better – 99% DCI-P3 is stable, as is 153% of the sRGB color volume – a first-class result for a gaming IPS model without the use of “quantum dots”.
In the special sRGB mode, the monitor emulates colors as accurately as possible. This allows the high-end gaming monitor to display a less saturated picture with normal color and contrast, without any issues. This is especially important if you do not want to look at an oversaturated picture.
After switching to the Reader eye strain reduction mode, the color gamut narrows to 132.3% of the sRGB color volume, compared to the factory setting of 150.5%. The visual saturation slightly decreases, the black point shoots “to the skies,” and the picture takes on a pronounced warm halftone. Since this preset isn’t meant for color-critical work, there’s no room for complaints — the manufacturer designed it exactly as intended.
For precise work with a wide color gamut, as well as for shades that exceed the standards under study, it is necessary to use suitable ICC/ICM profiles and software that provide regular support for the color management system (CMS). Among them are Adobe products, XnView, FastStone Viewer, Windows photo viewers (versions 7, 8, 10, and 11), as well as Opera, Firefox, Google Chrome, and others.
Brightness, Contrast, and Basic Color Rendering
The monitor under review has eight preset modes, of which we have selected only four of the most important and interesting. Additionally, we present the results after configuring and calibrating the 27-inch IPS gaming monitor without using LG’s factory software (due to specific reasons). By default, we use the “Player 1” profile with the following settings:
- Brightness: 100
- Contrast: 70
- Color temperature: User (50/50/50)
- Gamma: mode 2
- Black stabilizer: 50
During the calibration, the following settings were used to bring the white point to a brightness level of 100 nits and 6500K:
- Brightness: 20
- Contrast: 70
- Color temperature: User (48/46/49)
- Gamma: mode 2
- Black stabilizer: 50
Let us study the obtained results, presented in the table below:
With the default settings, the LG 27G850A-B’s brightness is set to the maximum available, at 470 nits — a level that is too high for long-term work. The contrast ratio, unfortunately, doesn’t reach the stated maximum of 2000:1, and reaches 1734:1 at best. In sRGB and DCI-P3 emulation modes, the brightness drops significantly, and the contrast ratio decreases to 1370-1430:1, which is still noticeably higher than that of the previous generation Nano IPS 4K. In reading mode, things are still much easier — 120:1, and that’s it.
The factory sets the white point to medium in both the default and emulation modes, while “Reading Mode” pushes it to a comfortable 5600K with a slight parasitic tint. In Player 1 and sRGB modes, the system sets gamma to medium, which reduces the visibility of shadow details. DCI-P3 tends to the standard of the same name (not the Display P3 option) and demonstrates an average of 2.66, compared to 2.6 by the standard.
The color temperature stability level at factory settings was high in both sRGB emulation mode and reading mode, making it ideal for use. After calibration, we achieved very high results from the LG monitor, surpassing the factory settings.
After returning to Player 1 mode and calibrating via the graphics card LUT, the 27G850A-B demonstrated 100 nits brightness with a contrast ratio of 1560:1, which is a good level for modern LG monitors.
Using the created color profile enabled the system to learn more accurately about the monitor’s capabilities in terms of color rendering and color gamut, resulting in a significant reduction in DeltaE deviations compared to those obtained in preset modes.
Now let’s move on to a deeper analysis.
With standard settings, the measured gamma curves are close to the reference curve, with an average gamma of 2.2; however, the LG 27G850A-B has issues with the distinguishability of shadows, as they are not distinct enough. There is a slight imbalance in RGB, and the majority of the gray wedge points are located on the border of DeltaE<10 in a dense group without a parasitic shade.
After calibration, the gamma curves returned to normal, and we got the correct image contrast on the screen. The white point and gray points were located in a dense group in the DeltaE < 3 area, ensuring the neutrality of the image on the screen without parasitic shades. The LG 27G850A-B 27-inch 4K UHD monitor offers ideal support for professional work, covering both DCI-P3 and sRGB color spaces.
In sRGB emulation mode, the factory sets the curves at the default level. As a result, the monitor doesn’t deliver the necessary improvements—contrast stays too high, and shadows remain poorly defined. If you do not work, but play, then for most users, this level of settings will be more than worthy.
If you’re looking for a punchy, high-contrast image, switch to the DCI-P3 emulation mode—it delivers bold colors, deep contrast, and a vivid look, though shadow detail takes a back seat.
Finally, the “Reading” mode dramatically changes the brightness and color temperature. This mode perfectly serves its purpose: reducing load, especially when large areas of deep shadows appear, which further lowers image contrast. It significantly raises the “zero black” point, cutting the contrast ratio by 12 to 14 times compared to the matrix’s potential. The gray wedge points shift in space and show a slight greenish tint. Is this mode suitable for long-term document work? Definitely.
Color Temperature Stability in Special Modes
Now let’s continue our LG 27G850A-B review, evaluating the stability of color temperature in special image modes.
Let us recall that, by default, the manufacturer has installed the “User” preset with RGB values of 50, 50, 50. Let us talk about the remaining CT presets with different values and advanced white point settings from the “Instructions” subsection:
The following points summarize essential aspects of the monitor’s color temperature settings:
- The User, Warm, and Manual 0 modes are nearly identical or even interchangeable. When choosing a color temperature for your display, these modes should be considered equivalent.
- Switching to Medium and Cool modes causes the color temperature to rise further; however, this also increases the maximum variance in color temperature, potentially affecting color consistency.
- The color temperature range can be expanded further using the fine-tuning options found in the “Instructions” section. There, you can select from 10 cooler and 8 warmer presets, enabling adjustments from 4,300K to 11,000K.
- Across all available modes, the color temperature remains stable, and the monitor maintains a high brightness level, ensuring consistent performance.
Contrast, Color Temperature Stability, and Brightness Change Range
We set the Player 1 mode to study the stability of contrast and the range of brightness changes. Then, we changed the “Brightness” value from 100% to 0% in 10-unit increments.
The resulting working brightness range with standard settings was 50-470 nits, with an average contrast ratio of 1720:1. The 27-inch 4K IPS monitor exceeded the manufacturer’s stated brightness level but was not as accurate in terms of black depth. However, compared to its predecessors, the result is, in any case, 70-80% higher – this is a victory!
The brightness reduction is almost linear and becomes completely linear after crossing the 80% limit—a common phenomenon for many models of the brand. At the same time, the contrast ratio is relatively stable throughout the entire range.
When the brightness was reduced from 100 to 0%, the color temperature changed by more than 600K – this is a visually noticeable change. It is worth considering this feature when setting up and subsequently adjusting the screen brightness.
At the upper limit, the 4K UHD monitor provides a high 470 nits, which will be more than enough for working in most conditions with bright external lighting. At the lower limit, the LG 27G850A-B review model will provide sufficient load reduction when working in low external lighting conditions. The consumer should not have any problems with choosing a comfortable brightness, especially since there is a reserve of contrast ratio, which can be slightly sacrificed for the sake of an even greater reduction in white brightness.
As for HDR, activating this mode enables the monitor to provide maximum brightness, ranging from 594 to 828 nits at peak, depending on the fill level (APL). Here, we can see some improvements over the previous generation of 4K Nano IPS; however, in real-world HDR content playback, you are unlikely to notice these changes.
Gradients Uniformity
With factory settings and in most preset modes, the LG 27G850A-B demonstrated gradient transitions that are pretty typical for this segment: relatively smooth, without parasitic shades and apparent “granulation”.
Increasing the bit depth to pseudo 10 bits (or even emulating 12-bit mode) has virtually no effect on the quality of gradients, especially in applications with 8-bit signal output, which was expected.
After manual adjustment, no visible changes are apparent. There are none when switching to the reading mode. Still, the calibration performed with edits in the LUT area of the graphics card resulted in sharper transitions and the appearance of parasitic shades and entire areas in the range of 0-40%. This is visible in the second photo above, indicating that the matrix is natively 8-bit – nothing more. However, LG does not hide this, and therefore, no questions arise.
Response time and Refresh rate
LG has long used the declared response time of 1 ms GtG, and the 27G850A-B monitor is no exception to this rule. At the same time, a footnote was preserved that the value can be obtained in the Faster mode (the latest response time option), and not with any other overclocking option.
To increase the speed of rotation of liquid crystals, the 4K HDMI 2.1 gaming monitor utilizes the classic OverDrive acceleration technology, which can be turned off or activated in one of four available positions (the default is “Fast”).
Upon visual inspection, it became clear that the model does not intend to become a leader among the numerous solutions on the market that operate at 240 Hz or higher. The product from LG demonstrated average results, which were reasonably expected for a solution based on Nano IPS Black. After all, IPS liquid crystal panels with increased black depth are generally less agile/speedy compared to solutions with more classic results of 800-1000:1.
There is no point in going down to the Off and Normal modes. They do not provide any advantages over the standard settings, and we did not observe any artifacts in either case.
The fourth mode, called Faster, will help make the picture a little sharper. The artifacts in it are strong and visible, but objects in motion become even sharper.
The new equipment allowed us to measure the monitor’s output lag time. In the case of our LG 27G850A-B review, when connected via DisplayPort with a frequency set to 240 Hz and NVIDIA G-Sync Compatible activated, it did not exceed 3.5 ms on average—an excellent result for a modern gaming monitor. If we switch to FHD mode, the lag time drops to 2.6 ms, which is better, but not essential, even for competitive games.
We would like to note that the 27G850A-B is officially certified as AMD FreeSync Premium Pro, indicating full support for the open VESA Adaptive-Sync standard. This certification also implies trouble-free operation with NVIDIA G-Sync in Compatible mode, as confirmed during actual testing of the monitor.
The LG 27G850A-B also exhibits no issues with frame skipping at the maximum vertical refresh rates of 240 Hz and 480 Hz, resulting in smooth and uninterrupted playback.
Viewing Angles
The LG 27G850A-B features a modern IPS panel that provides stable images when viewed from various angles.
The image above shows everything perfectly. With minor changes in the viewing angle in the horizontal plane, the picture on the screen changes practically imperceptibly. If you increase the angle to 30-45 degrees, the image becomes less contrasting, the saturation of some colors decreases, and shadows become lighter. With changes in the vertical plane, the picture on the screen deteriorates much faster and more strongly, which is normal.
Backlight Uniformity
The backlight and color temperature uniformity across the screen field were checked at 35 points with the monitor brightness set to 100 nits. The data from the central point was taken as the basis for all calculations (deviations).
With the brightness set, the average deviation from the center point was 7.7%, and the maximum was 21%. The overall result for a 27-inch 240Hz gaming monitor was average, which is quite common for many LG solutions.
The presented diagram of the surface clearly shows how the brightness level is concentrated across the matrix field. Everything is simple here – the further from the center, the darker it is, with no exceptions, as with some other monitors that have a different dependence of brightness change across the screen field. The darkest area of the sample we tested is the right side of the panel.
The photo above shows a white field with minimal corrections in a graphics editor for a more visual representation of what is happening on the screen in terms of the uniformity of the light field. The difference in brightness between the central zone, edges, and corners of the panel is visible. A reasonably large light zone is shifted to the upper left corner.
The difference in brightness and CT is even more noticeable on dark gray canvases, where all the problems become more obvious.
Now let’s look at a black background, assessing its “uniformity” using two photographs taken at different distances from the screen (~70 cm and 150 cm) so that you can determine the impact of the now boring Glow effect and find out the absolute uniformity of the backlight without taking it into account.
In the first case, Glow proved to be quite typical of IPS Black – four brightened corners with a warm parasitic shade and a brightness level that is maximally similar.
Now let’s move on to considering the color temperature uniformity across the entire screen area.
During the LG 27G850A-B review, manual settings of the CT were used to obtain 6500K; the brightness of the white field at the central point was maintained at 100 nits. The average deviation was 1.8%, with a maximum of 7.9%. The difference between the measured minimum and maximum was above the standard of 600K, resulting in a value below average.
The measurements taken confirmed the presence of the problem: our LG 27G850A-B review sample has a color temperature that increases diagonally, from the lower right to the upper left. This can be visually noticeable and add additional discomfort when working. You should take this aspect into account when choosing a sample, especially if you plan to work extensively with text, tables, read from the screen, or perform color correction.
Final Line
The new LG 27G850A-B is a long-awaited upgrade for the entire segment of 27-inch 4K IPS gaming LCD monitors. The manufacturer has not only increased the refresh rate but also taken care of increasing the depth of the black field, expanding the backlight capabilities in terms of brightness levels and color gamut. They attempted to upgrade the model to a higher class, thanks to improved materials and overall build quality.
The solution from LG, although not extremely fast by the standards of the gaming monitor market, will still become the main alternative to modern OLED for many, at least due to the reliability of LCD and IPS, in particular, without concerns about the health of pixels and the need for “maintenance” several times a day.
On the other hand, the overall stability of the 27G850A-B is compromised by the uniformity of the backlight in terms of brightness and color temperature. These are not the current OLED solutions, which have an almost ideal field; there is something to be aware of here. And therefore, the choice will still not be easy. The key is first to determine your budget and what you intend to use the monitor for before making a decision. For reference, LG 27G850A-B is priced at $885.30 on Amazon.com, $896.99 on B&H Photo, and £628 on Amazon.co.uk. Good luck choosing the right one!
