Your browser is not supported or outdated so some features of the site might not be available.

Cooler Master Tempest GP27U Monitor Review

Tested using Methodology v1.2
Reviewed Dec 16, 2022 at 11:35 am
Cooler Master Tempest GP27U Picture
8.4
Mixed Usage
8.6
Office
8.8
Gaming
7.9
Media Consumption
8.3
Media Creation
8.0
HDR

The Cooler Master Tempest GP27U is a premium 4k, 27-inch monitor. It features Mini LED backlighting with 576 local dimming zones, and as it's a high-end monitor, it has a ton of features for both productivity and gaming. It has a 160Hz max refresh rate that you can achieve over a DisplayPort connection, and it has HDMI 2.1 bandwidth that lets you take full advantage of the PS5 and Xbox Series X. Although it isn't officially certified by NVIDIA or AMD, both G-SYNC and FreeSync variable refresh rate (VRR) technology work. It has other features like a USB-C port that supports DisplayPort Alt Mode if you want to connect a laptop and has 90 W of power delivery. It also has a KVM switch that lets you control two devices with the same keyboard and mouse connected to it.

We tested the monitor using Firmware Version A, which came out on Dec. 2, 2022. It fixes many of the issues that users were reporting after the monitor's initial release and after a firmware update on Nov. 25, 2022. You can read more about it here.

Our Verdict

8.4 Mixed Usage

The Cooler Master GP27U is an impressive overall monitor. It's excellent for the office thanks to its sharp text clarity, high peak brightness to combat glare, and excellent ergonomics that make it easy to adjust. It's also excellent for gaming as it has HDMI 2.1 bandwidth for console gaming, a fast response time and low input lag for a responsive feel, and VRR support to reduce screen tearing. It displays a wide range of colors in SDR and HDR, which is important if you want to watch content, and it also displays deep blacks thanks to its decent Mini LED local dimming. While it's also great for content creators, you'll have to calibrate it for the best performance.

Pros
  • Incredible text clarity and image sharpness.
  • Easily gets bright enough to fight glare.
  • Excellent ergonomics.
  • HDMI 2.1 bandwidth for console gaming.
Cons
  • Colors wash out at an angle.
  • Needs calibration for most accurate colors.
  • KVM feature doesn't work well when switching sources.
8.6 Office

The Cooler Master GP27U is an excellent office monitor. The 27-inch screen and 4k resolution help deliver a high pixel density, resulting in sharp text, and you can open multiple windows at once. You won't have issues using it in a bright room either, as it easily gets bright enough to fight glare, and the reflection handling is fantastic. It also has decent wide viewing angles and excellent ergonomics if you need to adjust your screen to show someone else.

Pros
  • Incredible text clarity and image sharpness.
  • Easily gets bright enough to fight glare.
  • Excellent ergonomics.
  • Productivity features like USB-C input.
Cons
  • Colors wash out at an angle.
  • KVM feature doesn't work well when switching sources.
8.8 Gaming

The Cooler Master GP27U is excellent for gaming. You can take full advantage of the Xbox Series X or PS5 thanks to its HDMI 2.1 bandwidth, and you can play games with sharp detail thanks to its 4k resolution. It also has VRR support to reduce screen tearing with both AMD and NVIDIA graphics cards. The input lag is very low, and it has a quick response time that makes motion look smooth at any refresh rate. Lastly, it's a great choice for dark room gaming thanks to its decent local dimming feature for deep blacks.

Pros
  • HDMI 2.1 bandwidth for console gaming.
  • Quick response time at any refresh rate.
  • FreeSync and G-SYNC support.
  • Decent Mini LED local dimming feature.
Cons
  • More blooming when viewing off-center.
  • KVM feature doesn't work well when switching sources.
7.9 Media Consumption

The Cooler Master GP27U is very good for media consumption. Its 4k resolution helps result in sharp images with a ton of detail. Although it has a low native contrast ratio, its full-array Mini LED local dimming feature helps further improve the contrast for deep blacks with minimal blooming. However, while it has decent viewing angles, there's more blooming, and the image looks worse when viewing off-angle in a dark room, so it isn't good for watching content with a friend in a dark room.

Pros
  • Incredible text clarity and image sharpness.
  • Excellent ergonomics.
  • Decent Mini LED local dimming feature.
Cons
  • More blooming when viewing off-center.
  • Needs calibration for most accurate colors.
  • KVM feature doesn't work well when switching sources.
8.3 Media Creation

The Cooler Master GP27U is great for content creators. The 4k resolution delivers sharp images, and the 27-inch screen is big enough to work comfortably. It's also a great choice for use in well-lit rooms because it gets extremely bright. While it has excellent ergonomics that makes it easy to adjust and has decent viewing angles, the colors look washed out while viewing from the side, so it isn't good if you often need to share your screen with a client.

Pros
  • Incredible text clarity and image sharpness.
  • Easily gets bright enough to fight glare.
  • Excellent ergonomics.
Cons
  • Colors wash out at an angle.
  • Needs calibration for most accurate colors.
  • KVM feature doesn't work well when switching sources.
8.0 HDR

The Cooler Master GP27U is great for HDR. It gets very bright to deliver bright highlights and displays a wide range of colors with incredible color volume. While its native contrast ratio is low, it still delivers deep blacks thanks to its decent local dimming feature, and there's minimal blooming around bright objects. It also has fantastic gradient handling, meaning you won't see any banding with shades of similar colors, like in scenes with a sunset.

Pros
  • Decent Mini LED local dimming feature.
  • Displays wide range of colors in HDR.
  • Fantastic HDR peak brightness.
Cons
  • Some tone mapping issues.
  • Some settings locked in HDR.
  • KVM feature doesn't work well when switching sources.
  • 8.4 Mixed Usage
  • 8.6 Office
  • 8.8 Gaming
  • 7.9 Media Consumption
  • 8.3 Media Creation
  • 8.0 HDR
  1. Updated Dec 23, 2022: We tested the SDR peak brightness with local dimming disabled, and the input lag with it enabled. We were also able to reproduce a well-known issue with the KVM feature.
  2. Updated Dec 16, 2022: Review published.
  3. Updated Dec 14, 2022: Early access published.

Check Price

27" Tempest GP27U
SEARCH
Amazon.com
27" Tempest GP27U
SEARCH
BestBuy.com
27" Tempest GP27U
SEARCH
B&H

Differences Between Sizes And Variants

We tested the 27-inch Cooler Master Tempest GP27U, which is the only size and variant available for this model. It's one of two Mini LED monitors that Cooler Master has released to this point, with the Cooler Master Tempest GP27Q, and you can see the differences between them below.

Model Code Size Resolution Max Refresh Rate HDMI Type
GP27Q 27" 1440p 165Hz HDMI 2.0
GP27U 27" 4k 160Hz HDMI 2.1

Our unit was manufactured in September 2022, and you can see the label here. The full serial number is CMIGP27FUSUS1223700041. The review is with Firmware A, which Cooler Master released on Dec. 2, 2022, and there isn't a firmware number associated. There was a previous update on Nov. 25 that allowed VRR to work at the same time as local dimming, but this update brought a bunch of other issues, like black screens and connection issues, which were later fixed with the Dec. 2 update. You can read all about it in Cooler Master's subreddit here. Essentially, ensure you have the firmware updated to the latest version for the best performance, but if you encounter anything different on your unit, let us know.

Compared To Other Monitors

The Cooler Master Tempest GP27U is a great overall monitor that strikes a balance between excellent gaming performance, great HDR, and also offering productivity features. It gets very bright and delivers brighter highlights and more vivid colors compared to the Samsung Odyssey Neo G8 S32BG85. Although it initially had some bugs and took two firmware updates to fix most issues, it works as expected after the latest update, making it a cheaper option to the Samsung if you want a high-end 4k monitor for gaming that also delivers great HDR.

Also see our recommendations for the best 4k HDR monitors, the best HDR gaming monitors, and the best 4k gaming monitors.

Samsung Odyssey Neo G7 S32BG75

The Samsung Odyssey Neo G7 S32BG75 and the Cooler Master Tempest GP27U are both excellent 4k gaming monitors. They each have Mini LED local dimming that performs decently, and while the Cooler Master has lower native contrast, it still displays deep blacks like on the Samsung. The Cooler Master also has better motion handling and doesn't have the same bugs the Samsung has, like flicker with low frame rates, and it has a few extra features like a USB-C port and a KVM switch.

Gigabyte M28U

The Cooler Master Tempest GP27U is better overall than the Gigabyte M28U. The Cooler Master delivers better overall picture quality thanks to its decent local dimming feature, which helps it get brighter and display deeper blacks. It also has higher HDMI 2.1 bandwidth than the Gigabyte, so your graphics card doesn't need to use compression to achieve high-frame-rate signals. On the other hand, the Gigabyte has better color accuracy, and colors don't wash out when viewing off-center like on the Cooler Master.

Sony INZONE M9

The Cooler Master Tempest GP27U is better overall than the Sony INZONE M9. Although they each have full-array local dimming features, the Cooler Master uses Mini LED backlights to produce deeper blacks with less blooming, and it also gets much brighter in HDR for brighter highlights. The Cooler Master also has better motion handling and has better ergonomics that make it easier to adjust.

Samsung Odyssey Neo G8 S32BG85

The Samsung Odyssey Neo G8 S32BG85 and the Cooler Master Tempest GP27U are both excellent 4k gaming monitors. The main difference is that the Samsung monitor has a much higher 240Hz refresh rate, making it future-proof for 4k gaming at a high frame rate. They each have Mini LED local dimming that performs decently, and while the Cooler Master has lower native contrast, it still displays deep blacks like on the Samsung. The Cooler Master also has better motion handling and doesn't have the same bugs the Samsung has, like flicker with low frame rates, and it has a few extra features like a USB-C port and a KVM switch.

LG 32GQ950-B

The Cooler Master Tempest GP27U and the LG 32GQ950-B are both 4k monitors with a max refresh rate of 160Hz, but there are a few differences between them. The Cooler Master delivers better overall picture quality as it displays deeper blacks thanks to its better local dimming feature, and also gets much brighter in HDR for brighter highlights. The Cooler Master also has better reflection handling if you want to use it in a well-lit room. However, the LG has more accurate colors and wider viewing angles, so it's a better choice if your work requires accurate colors.

+ Show more

Test Results

perceptual testing image
Design
Design
Style
Curved
No
Curve Radius
Not Curved

The Cooler Master GP27U has a rather simple design with a hexagonal stand. It's mainly black with a bit of lighting in the back.

7.0
Design
Build Quality

The build quality is okay. The plastic materials feel cheap and flex easily. The cable management clip also comes off easily. Luckily, the base of the stand is aluminum and feels solid, but there's still wobble if you have the monitor on an unstable desk.

8.6
Design
Ergonomics
Height Adjustment
4.3" (11.0 cm)
Tilt Range
-20° to 5°
Rotate Portrait/Landscape
Yes, Both Ways
Swivel Range
-30° to 30°
Wall Mount
VESA 100x100

The Cooler Master GP27U has excellent ergonomics, as it's easy to adjust to an ideal position. The stand also offers basic cable management through a clip, but the clip comes off easily if you pull the cables.

Design
Stand
Base Width
11.6" (29.4 cm)
Base Depth
10.8" (27.4 cm)
Thickness (With Display)
6.3" (16.0 cm)
Weight (With Display)
15.2 lbs (6.9 kg)

The base of the stand is aluminum and has a hexagonal shape. Because it takes up a lot of space, you need a big desk if you want space for your keyboard and mouse in front.

Design
Display
Size
27"
Housing Width
24.3" (61.6 cm)
Housing Height
14.3" (36.3 cm)
Thickness (Without Stand)
2.8" (7.0 cm)
Weight (Without Stand)
11.7 lbs (5.3 kg)
Borders Size (Bezels)
0.2" (0.5 cm)
Design
Controls

There's a joystick on the back right side to control the on-screen display or power it off.

Design
In The Box
Power Supply
External Brick

  • Power supply and cable
  • HDMI cable
  • DisplayPort cable
  • USB-B to USB-A cable
  • USB-C to USB-C cable
  • User documentation and guides

Picture Quality
6.4
Picture Quality
Contrast
Native Contrast
1,072 : 1
Contrast With Local Dimming
2,209 : 1

The Cooler Master GP27U has an alright native contrast ratio. It's mainly limited by its IPS panel, which has low native contrast, but the full-array Mini LED local dimming feature helps further improve it. Exceptionally, we also measured the contrast using the TV Test Bench 1.9 methodology, which uses a real scene photo instead, as you can see here. You can see the results of that below:

  • Contrast: 69,867:1
  • Local Contrast: 2,525:1

The Contrast uses the average black levels of the four black corners, while the Local Contrast is the contrast between the white and black levels closer to the cave. However, these numbers aren't comparable to the results in the review because they're tested differently, and the local dimming interacts with the checkerboard pattern differently than real content. In this case, it can effectively turn off the dimming zones in the four corners of the cave scene, but it can't do that with the black squares around the center white square in the checkerboard.

7.0
Picture Quality
Local Dimming
Local Dimming
Yes
Backlight
Full-Array

The Cooler Master GP27U has a decent full-array Mini LED local dimming feature. There are 576 zones, and the recommended setting is with Local Dimming on 'High', and you can enable it in SDR and HDR. It's better than any edge-lit monitor and keeps up with other Mini LED monitors like the Samsung Odyssey Neo G8 S32BG85. The screen is uniform, and the local dimming helps eliminate any backlight bleed you see with it disabled. The algorithm keeps up with fast-moving objects well, but at times you can see that it changes zones too quickly, which can get distracting. There's minimal black crush on 'High', as you can see here, so it preserves details well, and there isn't too much blooming either. There's more black crush with the local dimming set to 'Low' and the screen isn't as bright.

The local dimming performs best when you're viewing from directly in front because there's a lot of blooming and the overall image looks worse when moving off-center, meaning it isn't ideal for watching content with a friend. You can see an example of the blooming when viewing off-center here.

Originally, you couldn't enable the local dimming at the same time as the variable refresh rate (VRR), but Cooler Master has since released an update to fix that on Nov. 25, 2022, and you can now use both at the same time.

9.3
Picture Quality
SDR Brightness
Real Scene
1,064 cd/m²
Peak 2% Window
1,109 cd/m²
Peak 10% Window
1,492 cd/m²
Peak 25% Window
1,285 cd/m²
Peak 50% Window
1,192 cd/m²
Peak 100% Window
1,423 cd/m²
Sustained 2% Window
1,088 cd/m²
Sustained 10% Window
1,442 cd/m²
Sustained 25% Window
1,271 cd/m²
Sustained 50% Window
1,188 cd/m²
Sustained 100% Window
1,273 cd/m²
ABL
0.015
Minimum Brightness
69 cd/m²

The SDR peak brightness is incredible, and you won't have any issues using it in a bright room. Enabling the local dimming helps make it bright, and there isn't too much distracting change in brightness between different scenes either. Unfortunately, the minimum brightness is a bit high if you work in a dark room and you're sensitive to light, and this is also with local dimming disabled.

These results are from after calibration in the 'Standard' Picture Mode with the Brightness at its max and Local Dimming on 'High'. It was tested with Firmware A that was updated on Dec. 2, 2022, and before the update the Real Scene brightness was 661 cd/m².

We also measured the peak brightness with local dimming disabled, but all other settings the same. With a real scene, the GP27U reaches a peak brightness of 594 cd/m², and with our test slides it maintains about 604 cd/m² across all window sizes.

9.0
Picture Quality
HDR Brightness
VESA DisplayHDR Certification
No Certification
Real Scene
981 cd/m²
Peak 2% Window
1,007 cd/m²
Peak 10% Window
1,286 cd/m²
Peak 25% Window
1,120 cd/m²
Peak 50% Window
1,043 cd/m²
Peak 100% Window
1,163 cd/m²
Sustained 2% Window
1,001 cd/m²
Sustained 10% Window
1,244 cd/m²
Sustained 25% Window
1,108 cd/m²
Sustained 50% Window
1,038 cd/m²
Sustained 100% Window
1,158 cd/m²
ABL
0.011

The HDR peak brightness is fantastic. It gets bright enough to make highlights pop and maintains its brightness even with larger highlights, which is great. The EOTF also follows the target well until there's a sharp roll-off at the peak brightness, causing a loss of fine details in bright scenes.

These results are with Firmware A, which was updated on Dec. 2, 2022. This update causes the brightness to go down as the monitor reached a peak of 1,400 cd/m² before any update. After the update released on Nov. 25, the Real Scene brightness was 1,228 cd/m². However, we also encountered some issues measuring the Real Scene brightness because the Blu-ray player we normally test with didn't work, so we used a second Blu-ray player. Using the same video for the Real Scene brightness with Windows HDR, the brightness is 1,125 cd/m². While the overall brightness is still fantastic, it isn't as bright as it was before the updates.

Unfortunately, after the firmware update on Dec. 2, 2022, the Gamma, Color Domain, and Color Space settings are locked at their defaults when in HDR, and you can't change them.

7.0
Picture Quality
Horizontal Viewing Angle
Color Washout From Left
27°
Color Washout From Right
32°
Color Shift From Left
39°
Color Shift From Right
45°
Brightness Loss From Left
31°
Brightness Loss From Right
36°
Black Level Raise From Left
70°
Black Level Raise From Right
70°
Gamma Shift From Left
30°
Gamma Shift From Right
35°

The Cooler Master GP27U has a decent horizontal viewing angle. It's fine if you have to share work with a coworker or client, but not if they need to see accurate colors, because the colors start to shift quickly. As explained in the Local Dimming section, the image looks worse in dark scenes with local dimming enabled and when viewing off-center as there's blooming.

7.5
Picture Quality
Vertical Viewing Angle
Color Washout From Below
31°
Color Washout From Above
35°
Color Shift From Below
54°
Color Shift From Above
58°
Brightness Loss From Below
33°
Brightness Loss From Above
37°
Black Level Raise From Below
70°
Black Level Raise From Above
70°
Gamma Shift From Below
40°
Gamma Shift From Above
44°

The vertical viewing angle is good. You won't have issues using it when viewing it from above, like when you're standing up.

8.0
Picture Quality
Gray Uniformity
50% Std. Dev.
2.991%
50% DSE
0.142%

The gray uniformity is great. There's minimal dirty screen effect in the center, which is great for browsing the web or watching sports, but the edges are darker than the rest of the screen.

7.0
Picture Quality
Black Uniformity
Native Std. Dev.
1.684%
Std. Dev. w/ L.D.
0.471%

The Cooler Master GP27U has remarkable black uniformity with the local dimming feature enabled. There's minimal blooming around bright objects, and blacks look deep. You need to set Local Dimming to 'High' for the best performance, as disabling it results in a blue tint and backlight bleed.

6.6
Picture Quality
Color Accuracy (Pre-Calibration)
Picture Mode
Standard (sRGB)
sRGB Gamut Area xy
95.1%
White Balance dE (Avg.)
7.83
Color Temperature (Avg.)
6,060 K
Gamma (Avg.)
2.28
Color dE (Avg.)
4.58
Contrast Setting
70
RGB Settings
50-50-50
Gamma Setting
2.2
Brightness Setting
50
Measured Brightness
350 cd/m²
Brightness Locked
No

The accuracy before calibration is alright. The white balance is noticeably off, causing the entire image to look inaccurate, and most colors are off too. The color temperature is warmer than the 6500K target, giving the image a red tint, and gamma doesn't follow the target sRGB curve well, as most scenes are too dark.

These results are with Firmware A after the Dec. 2, 2022 update. This update locks the colors to the sRGB color space well and lets you change any setting you like while in the sRGB mode. Initially, you couldn't change the Color Temperature setting, then after the update on Nov. 25, 2022, the sRGB clamp broke, causing the sRGB coverage area to be 159.1%.

9.4
Picture Quality
Color Accuracy (Post-Calibration)
Picture Mode
Standard
sRGB Gamut Area xy
102.0%
White Balance dE (Avg.)
1.18
Color Temperature (Avg.)
6,491 K
Gamma (Avg.)
2.18
Color dE (Avg.)
0.77
Contrast Setting
70
RGB Settings
50-48-49
Gamma Setting
2.2
Brightness Setting
4
Measured Brightness
104 cd/m²
ICC Profile
Download

The accuracy after calibration is fantastic and removes nearly all inaccuracies with the white balance, color, color temperature, and gamma.

9.9
Picture Quality
SDR Color Gamut
sRGB Coverage xy
99.6%
sRGB Picture Mode
Standard
Adobe RGB Coverage xy
99.6%
Adobe RGB Picture Mode
Standard

The SDR color gamut is simply outstanding. It has perfect coverage of both the commonly-used sRGB color space and the Adobe RGB color space used in some photo editing, but it oversaturates reds in that color space.

9.9
Picture Quality
SDR Color Volume
sRGB In ICtCp
99.0%
sRGB Picture Mode
Standard
Adobe RGB In ICtCp
98.8%
Adobe RGB Picture Mode
Standard

The Cooler Master GP27U has an outstanding SDR color volume. Besides perfectly dark colors, it displays all colors very well at various luminance levels.

9.3
Picture Quality
HDR Color Gamut
Wide Color Gamut
Yes
DCI-P3 Coverage xy
97.3%
DCI-P3 Picture Mode
Game
Rec. 2020 Coverage xy
82.7%
Rec. 2020 Picture Mode
Game

The HDR color gamut is fantastic. It has near-perfect coverage of the common DCI-P3 color space and decent coverage of the wider Rec. 2020 color space. However, tone mapping is off with both, particularly in Rec. 2020, so there's a loss of details with saturated colors.

Unfortunately, after the firmware update on Dec. 2, 2022, the Gamma, Color Domain, and Color Space settings are locked at their defaults in HDR, and you can't change them.

8.8
Picture Quality
HDR Color Volume
DCI-P3 In ICtCp
89.2%
DCI-P3 Picture Mode
Game
Rec. 2020 In ICtCp
77.1%
Rec. 2020 Picture Mode
Game

The HDR color volume is excellent. It displays colors at a wide range of luminance levels well, but it's limited by its incomplete color gamut.

7.3
Picture Quality
Reflections
Screen Finish
Matte
Total Reflections
5.5%
Indirect Reflections
3.2%
Calculated Direct Reflections
2.4%

The Cooler Master GP27U has decent reflection handling. Although it struggles to reduce distracting reflections from some strong light sources, it still gets bright enough to fight even intense glare.

9.0
Picture Quality
Text Clarity
Pixel Type
IPS
Subpixel Layout
RGB

Thanks to the high resolution and high pixel density, the text clarity is incredible. Enabling Windows ClearType (top photo) helps improve the clarity of certain letters, but you likely won't need it anyways. These pictures are with Windows 10, and you can see what it looks like with Windows 11:

9.6
Picture Quality
Gradient
Color Depth
10 Bit

The gradient handling is fantastic. You won't see banding between shades of the same color, like in a sunset.

Motion
8.5
Motion
Refresh Rate
Native Refresh Rate
160 Hz
Max Refresh Rate
160 Hz
Max Refresh Rate Over DP
160 Hz
Max Refresh Rate Over HDMI
144 Hz
Max Refresh Rate Over DP @ 10-bit
160 Hz
Max Refresh Rate Over HDMI @ 10-Bit
144 Hz

To achieve the max refresh rate over DisplayPort, you'll need to update the firmware because, initially, you couldn't reach 160Hz over DisplayPort. Cooler Master released an update on Nov. 25, 2022 to fix that.

Motion
Variable Refresh Rate (VRR)
FreeSync
Compatible (Tested)
G-SYNC
Compatible (Tested)
VRR Maximum
160 Hz
VRR Minimum
< 20 Hz
VRR Supported Connectors
DisplayPort, HDMI
Variable Refresh Rate
Yes

Although the Cooler Master GP27U isn't certified by either NVIDIA or AMD, its VRR support works both with AMD and NVIDIA graphics cards. It also supports Low Framerate Compensation for the VRR to continue working even when the frame rate drops too low. It also works with G-SYNC and FreeSync over HDMI and DisplayPort across its entire refresh rate range.

Originally, you couldn't enable the local dimming at the same time as VRR, but after a firmware update on Nov. 25, 2022, you can now do that. VRR and HDR are supported at the same time.

9.2
Motion
Response Time @ Max Refresh Rate
Recommended Overdrive Setting
Normal
Rise / Fall Time
3.4 ms
Total Response Time
6.2 ms
Overshoot Error
1.3%
Worst 3 Rise / Fall Time
4.2 ms
Worst 3 Total Response Time
8.7 ms
Worst 3 Overshoot Error
9.4%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
OffChartTablePhoto
NormalChartTablePhoto
AdvancedChartTablePhoto
UltrafastChartTablePhoto
DynamicChartTablePhoto
User (30)ChartTablePhoto

The response time at its max refresh rate of 160Hz is fantastic. There's minimal motion blur, and fast-moving objects look incredible. There are various overdrive settings, including a custom one called 'User', that you can adjust from 0 to 100. Setting it to '30' is the recommended setting at its max refresh rate if you're going to use the mode, but the 'Normal' setting still has a faster response time with less overshoot. It's unclear what exactly the 'Dynamic' mode does, but it performs like 'Advanced'.

9.0
Motion
Response Time @ 120Hz
Recommended Overdrive Setting
Off
Rise / Fall Time
3.7 ms
Total Response Time
7.5 ms
Overshoot Error
0.0%
Worst 3 Rise / Fall Time
5.5 ms
Worst 3 Total Response Time
9.5 ms
Worst 3 Overshoot Error
0.0%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
OffChartTablePhoto
NormalChartTablePhoto
AdvancedChartTablePhoto
UltrafastChartTablePhoto
DynamicChartTablePhoto
User (15)ChartTablePhoto
User (30)ChartTablePhoto

The response time at 120Hz is once again fantastic. However, it's better to leave the overdrive setting to 'Off' because the other settings have too much overshoot. Setting the 'User' mode to '15' actually performs a lot like 'Off', but it has a slightly slower response time.

8.6
Motion
Response Time @ 60Hz
Recommended Overdrive Setting
Off
Rise / Fall Time
3.8 ms
Total Response Time
9.4 ms
Overshoot Error
0.0%
Worst 3 Rise / Fall Time
5.5 ms
Worst 3 Total Response Time
16.6 ms
Worst 3 Overshoot Error
0.0%

Overdrive SettingResponse Time ChartResponse Time TablesMotion Blur Photo
OffChartTablePhoto
NormalChartTablePhoto
AdvancedChartTablePhoto
UltrafastChartTablePhoto
DynamicChartTablePhoto
User (15)ChartTablePhoto
User (30)ChartTablePhoto

The response time at 60Hz remains excellent, as long as you leave the overdrive setting disabled as the other settings have more overshoot, including 'User'.

Motion
Backlight Strobing (BFI)
Backlight Strobing (BFI)
No BFI
Maximum Frequency
N/A
Minimum Frequency
N/A
Longest Pulse Width Brightness
N/A
Shortest Pulse Width Brightness
N/A
Pulse Width Control
No BFI
Pulse Phase Control
No BFI
Pulse Amplitude Control
No BFI
VRR At The Same Time
No BFI

The Cooler Master GP27U doesn't have an optional backlight strobing feature to reduce persistence blur.

10
Motion
Image Flicker
Flicker-Free
Yes
PWM Dimming Frequency
0 Hz

The Cooler Master GP27U is flicker-free when you have local dimming disabled, which helps reduce eye strain. However, there's flicker once you enable the local dimming, but it's so high that you won't even notice it. You can see the graph for it here.

Inputs
8.9
Inputs
Input Lag
Native Resolution @ Max Hz
3.9 ms
Native Resolution @ 120Hz
4.8 ms
Native Resolution @ 60Hz
8.8 ms
Backlight Strobing (BFI)
N/A

The Cooler Master GP27U has low input lag for a responsive feel, and you won't notice any delay. The posted results are with local dimming disabled, but we also took extra measurements with it enabled and found that it adds about 0.2ms, which is negligible.

9.0
Inputs
Resolution And Size
Native Resolution
3840 x 2160
Aspect Ratio
16:9
Megapixels
8.3 MP
Pixel Density
163 PPI
Measured Screen Diagonal
26.9"
Screen Area
310 in²
10
Inputs
PS5 Compatibility
4k @ 120Hz
Yes
4k @ 60Hz
Yes
1440p @ 120Hz
Yes
1440p @ 60Hz
Yes
1080p @ 120Hz
Yes
1080p @ 60Hz
Yes
HDR
Yes
VRR
Yes

The Cooler Master GP27U works well with the PS5 as it has HDMI 2.1 bandwidth, allowing you to take full advantage of the PS5. It originally worked without issue after the monitor's release, but a firmware update on Nov. 25, 2022, broke the PS5 support as 4k no longer worked. However, Cooler Master released another firmware update on Dec. 2, and there aren't any problems with the console.

10
Inputs
Xbox Series X|S Compatibility
4k @ 120Hz
Yes
4k @ 60Hz
Yes
1440p @ 120Hz
Yes
1440p @ 60Hz
Yes
1080p @ 120Hz
Yes
1080p @ 60Hz
Yes
HDR
Yes
VRR
Yes

The monitor works with any signal from the Xbox Series X, and unlike with the PS5, there aren't any issues with any of the firmware updates.

Inputs
Inputs Photos
Inputs
Video And Audio Ports
DisplayPort
1 (DP 1.4)
Mini DisplayPort
No
HDMI
2 (HDMI 2.1)
HDMI 2.1 Rated Speed
48Gbps (FRL 12x4)
DVI
No
VGA
No
Daisy Chaining
No
3.5mm Audio Out
1
3.5mm Audio In
No
HDR10
Yes
3.5mm Microphone In
No
Inputs
USB
USB-A Ports
2
USB-A Rated Speed
5Gbps (USB 3.2 Gen 1)
USB-B Upstream Port
Yes
USB-C Ports
1
USB-C Upstream
Yes
USB-C Rated Speed
5Gbps (USB 3.2 Gen 1)
USB-C Power Delivery
90W
USB-C DisplayPort Alt Mode
Yes
Thunderbolt
No

The DisplayPort Alt Mode with the USB-C input lets you display an image from a compatible laptop, and the 90 W of power delivery is enough to charge even most laptops while you're using it.

Inputs
macOS Compatibility

The Cooler Master GP27U works well with M1 MacBooks. The VRR and HDR work well and you can close the laptop's lid while working on the monitor as long as you're using the USB-C connection. Windows return to their original position when opening the lid, too. You also need to make sure you have the KVM settings enabled for everything to work.

Features
Features
Additional Features
Speakers
Yes
RGB Illumination
Fixed (On/Off)
Multiple Input Display
No
KVM Switch
Yes

The Cooler Master GP27U has a few extra features, including:

  • Black Stabilization: Adjusts gamma to make it easier to spot players in dark scenes.
  • Blue Light Filter: Removes blue light to help reduce eye strain.
  • Crosshair: Adds a virtual crosshair to any game that your system can't detect.
  • FPS Counter: Shows the current frame rate of your source.
  • Timer Adds a virtual crosshair on the screen.

Its KVM switch lets you control two devices with the same keyboard and mouse. Unfortunately, there are some issues with it, as the connected devices completely disconnect when you switch sources, so your source thinks it's a new device as it has to redo the device handshake. It also redoes the handshake when going into a full screen game or changing the resolution of the screen. One particularly annoying issue with this occurs when you have headphones connected, as it even switches to the built-in speakers for a few seconds before switching back to the headphones.

Features
On-Screen Display (OSD)

Discussions