Cooler Master Tempest GP27U Review: The high resolution of 4K gaming monitors is wonderful for fidelity, but a correct HDR implementation takes precedence when it comes to delivering a next-level visual experience. Unfortunately, a lot of gaming monitors produce mediocre HDR with poor implementations of dimming zones, low peak brightness, and limited contrast that really fails to make images jump.
Not one of them is the Cooler Master Tempest GP27U. For $1,000, you can get a 4K/160Hz gaming display with powerful local MiniLED dimming. It isn’t cheap, but it also isn’t attempting to get by with poor specifications.
Cooler Master Tempest GP27U – Design And Features
This machine, the Cooler Master Tempest, is understated. The panel section isn’t very crowded; there are only a few accent lights and a few chic cutaways. The stand, meanwhile, consists of a straightforward vertical pillar that emerges from a hexagonal base that resembles the Cooler Master logo.
Conveniently, the stand already has a cable tie attached. Despite having a straightforward design, the stand has several adjustments and is quite solid.
However, the display has a lot of features and a wide range of connectors, so most people should be content. For consoles, a pair of HDMI 2.1 connections that support 4K/120Hz are ideal.
The 4K/160Hz stream is ready to be handled by a DisplayPort 1.4 connector. Additionally, a USB-C connector that can deliver 90W of power, as well as handle display and USB data, is there. There’s not much more you could ask for if you add a two-port USB hub.
The monitor’s controls are all located on a single joystick that is located around the rear. This joystick is used to control everything, including power and settings. The display seems to have trouble waking up with my computer anytime it is idle, and it will lock itself into a power-saving mode and fail to detect any input.
This is one particular annoyance that results from this. The joystick was continually unresponsive while it was in this mode, making it impossible for me to access settings, switch inputs, or restart the monitor. As a result, the power cord and DisplayPort cable had to be unplugged and replugged into the monitor’s back. Your results may differ.
The monitor takes an external power brick and considering its 240-watt rating, it’s not a small one, which will not appeal to those who enjoy a neat desk layout. There is some heat associated with all that power.
As I played with the joystick, I became more aware of the heat and discovered that the bottom corners were a particular hotspot, with temperatures rising as high as 120 degrees Fahrenheit there. However, given the monitor’s impressive performance, heat is to be expected.
By combining 4K at 160Hz with extremely bright display technology, the Tempest practically necessitates a lot of electricity.
Although local dimming and variable refresh rates are supported by the Tempest, they cannot be used simultaneously at launch.
This problem has been resolved by a firmware update, and installing the update is straightforward using a USB drive and one of the ports on the back of the monitor.
The monitor has speakers, but they are of the standard last-ditch variety. In a calm environment, you will be able to hear what you’re listening to, but you won’t want to watch movies, listen to music, or play video games while depending on them.
Cooler Master Tempest GP27U – Testing
With its default settings, the Cooler Master Tempest GP27U is a color king, covering 100% of the sRGB and Adobe RGB color spaces, as well as 98% of DCI-P3 and 97% of NTSC. It supports that with flawless accuracy, with each hue achieving an average accuracy dE of 0.73 and keeping an accurate dE of less than 1.51. In other words, you’d have to be a machine to notice any flaws.
However, performance straight out of the box isn’t the whole story. There are several things missing in this situation. The maximum brightness is 254.8 nits, and the contrast is a pitiful 850:1. This is due to the fact that the delivered presets only have the brightness set to 35% and disable the monitor’s industry-leading local dimming.
The monitor can reach a blinding 875.7-nit peak brightness and a 2930:1 contrast ratio by simply turning the brightness up to 100% and the maximum local dimming level.
This contrast performance occurs when there are black portions on the screen alongside other sections of piercingly bright white.
When black parts are farther away from the display’s bright sections, local dimming actually makes it possible for them to get even darker, providing a contrast ratio of 33,070:1 between a nearly full white screen that reaches 932.6 nits and a nearly full black screen that dims to just 0.03 nits.
Gamut and accuracy are slightly reduced by this setting, but neither of the color spaces falls below 97% coverage, and accuracy is nevertheless maintained below an average dE of 3.
Unfortunately, HDR somewhat ruins the show. Contrary to popular belief, enabling it narrows the color spectrum of the display, bringing Adobe RGB coverage down to 79%, DCI-P3 coverage up to 81%, and NTSC down to 74%.
Similar problems arise with color accuracy, which now has a dE average of 2.46. Even yet, the SDR color fidelity was still extremely impressive. But HDR offers advantages as well. I was able to record a peak brightness of 958 nits, which may or may not apply to a sizable portion of the panel.
Strangely, I was never able to get the monitor to display at its maximum brightness, which is 1200 nits. The greatest figure I have ever seen was 958 nits, which could be attained between 9% and 25%. Larger windows might not have had enough power to drive all those pixels at that brightness level, and it appeared that smaller windows wouldn’t be able to muster enough brightness from the backlights to reach the same peak.
The local dimming on the Cooler Master Tempest GP27U works extremely well when activated, greatly enhancing contrast, but despite having mind-boggling 576 zones, some obvious blooming still appears around the zones. On a dark background, highlights show localized blooming.
The boundaries where a black background meets a bright piece of content also exhibit blooming, however, this is more difficult to discern. As shifting brightness in the screen space around that area can change the contrast between the text and background, the local dimming can have certain unfavorable consequences around text on a gray background.
It’s impressive how well the Cooler Master Tempest GP27U handles motion. In the Blurbusters UFO test, the ghosting trail left by the UFO is quite faint. Even though some of the UFO’s details are tougher to see when it is moving, it doesn’t appear to be too hazy. Additionally, there is no indication of pixel overshoot.
With the overdrive settings that came pre-installed, that performance was possible. I was able to reduce ghosting even more with a few manual adjustments to overdrive, although going too far caused some overshoot.
Cooler Master Tempest GP27U – Gaming
Far while there was plenty to like based just on objective criteria, the Tempest is even better when used for gaming, which is its main purpose.
Simply put, this monitor’s use of HDR and local dimming is fantastic for entertaining. While HDR and local dimming are turned on, visual irregularities are more obvious when attempting to work and visit the internet with the display. However, turning them off again until entertainment time solves the problem.
In some circumstances, the Tempest GP27U’s performance can nearly be compared to OLED, with broad black areas falling into perceptibly absolute darkness and highlights illuminating at the monitor’s maximum brightness.
I even watched a demo movie for an LG OLED TV and was astonished by how well this monitor could display it. I’m pretty pleased by how close Cooler Master managed to get, especially considering that OLED has its own quirks to cope with. I just evaluated an OLED display for Asus.
When used alongside an OLED panel, the monitor occasionally demonstrates the limitations of its local dimming zones. For instance, when little highlights are displayed on a dark backdrop, the area around the highlight will bloom. This is most apparent while the highlights are changing since the blooming appears and disappears as one area changes from light to darkness.
When used in video games, the Tempest GP27U’s flaws are reduced to minor infractions. Its lack of precise color accuracy in HDR seldom prevents it from producing beautiful gaming images. In a hectic firefight in Warzone 2.0, the blooming from local dimming visible on starfield-style visuals is rarely a nuisance.
And even while I couldn’t get the entire screen to shine at 1,200 nits, a tiny highlight can still burn my eyes, especially when it contrasts with the deep darkness the monitor can produce.
I was able to keep up with the action in Overwatch 2 and Warzone 2.0 because of its quick refresh rate and respectable pixel response time. Warhammer 40,000: Darktide’s filthy environs are amplified beautifully by the game’s rich contrast and vibrant HDR.
Only the Alienware AW3423DW and the Asus ROG Swift PG42UQ displays I’ve tried, I can say with some degree of confidence, could compare to this display. Both are more expensive and use OLED technology (QD-OLED in the case of Alienware). Choosing between these three monitors would depend on your priorities, but each offers advantages over the others. However, the Tempest GP27U delivers a high-class experience without a doubt.
Its main competitors are probably LG’s upcoming 1440p/240Hz OLED gaming monitor and Cooler Master’s own GP27Q, which is nearly identical to the GP27U but with a slightly quicker 1440p panel and a much more alluring $499 price tag.