Cooler Master GZ2711 OLED monitor review: OLED perks but overpriced
Reviewed By: Aaron Ritchie
Table of Contents
The Tempest GZ2711 is Cooler Master's first foray into the OLED monitor space. It comes with the size and resolution that is becoming the new standard for most gaming monitors, specifically 27 inches and 2560 x 1440 (i.e. QHD/1440p). Released in Q1 2024, it joins the other Tempest models in the line-up, which also includes IPS, VA, and Mini-LED variants.
The specific panel this model comes with is an LG-made WOLED: the LM270AHQ-ERG2, which was first seen in the LG Ultragear 27GR95QE-B, one of the first 240Hz OLED monitors to hit the market back in 2023. Coming with the same 240Hz maximum refresh rate, alongside the lightning-fast response time that OLED panels are known for, the specifications of this display look enticing for competitive gamers, as well as those who want to enjoy excellent contrast ratio and deep blacks when viewing movies or more immersive single-player titles.
That being said, the market for 240Hz OLED monitors at this size and resolution is more crowded than it was a couple of years ago (with options like the Gigabyte AORUS FO27Q3 also vying for position). Let's see how this one held up in our testing.
- Refresh rate: 240Hz
- Response time: 0.03ms
- Screen Size: 26.5″
- Resolution : 2560 x 1440
- Panel type: WOLED (LG.Display LM270AHQ-ERG2)
- I/O ports: 2x DP 1.4, 2x HDMI 2.1, 1x USB-C (DP & 96W PD), 2x USB-A 3.2 Gen 1, 1x USB-B 3.2 upstream, 1x 3.5 mm audio output
A fast gaming monitor with the terriffic response time you'd expect from an OLED display, a sturdy metal base, and a good selection of ports, the Cooler Master Tempest GZ2711 OLED is by no means a bad monitor if you can get one at a cheap price. Unfortunately it lags behind the competition in too many areas to justify its usual asking price, in particular the mediocre color accuracy, HDR implementation, and lack of OLED burn-in warranty coverage.
- 240Hz refresh rate
- Excellent response time & motion clarity
- Sturdy stand
- Matte coating reduces glare
- 96W USB-C Power Delivery & KVM switch
- A good array of ports
- Inferior HDR
- Peak SDR brightness low as with other WOLEDs
- Color accuracy sub-par
- Seemingly no OLED burn-in cover in warranty
- Unintuitive controls
- Text legibility could be better
- Not the cheapest
Pricing & availability
When it originally came to market in March 2024, the Tempest GZ2711 OLED 240Hz variant retailed for $900, which is a bit above the average compared to the competition. You can pick up the Gigabyte AORUS FO27Q3 for instance for around the $650 mark, and this comes with a panel capable of reaching a higher 360Hz refresh rate (though it comes with inferior USB-C power delivery and lacks a KVM switch). It's not that easy to find one of these monitors across a lot of retailers now, and where you can the price can vary wildly between $700–$1,000.
Design & specifications
The panel of the GZ2711 comes with a fairly noticeable matte screen coating to reduce glare, though this obviously makes for a muddier picture with less vibrant colors than on a glossy screen. The bezels around the screen are all nice and thin, with the only exception to this being a small protrusion on the ‘chin' of the screen, which houses the OSD controls round the back and a power light on the front.
As you'd expect from an OLED screen with no need for backlighting, the majority of the screen is pretty slender, with a thicker central section round the back which houses the I/O. The back of the screen is of a matte black plastic, with the Cooler Master logo in the centre and diagonal RGB light strips running down either side of the thicker central part.
The metal base and stand column feel very solid and sturdy, although they don't look the nicest (in our subjective opinion). Although the base increases the weight and makes this quite a heavy monitor, for its size, this could be considered a good thing in terms of keeping the screen stable and secure. There is a quick-release panel on the back that can be used to replace the stand with a 100 x 100mm VESA mount.
The power adapter also weighs a lot more than average as well, being twice as big as many competing OLED laptops of the same size and a bit cumbersome.
Adjustability is as expected, with a Tilt of -5° to +15°, a swivel of ±15°, height adjustment of 0-110mm, and a pivot either way of 90°.
The OSD controls consist of a single joystick behind the front middle of the screen, with a power button to the right of it.
The amount of connections you get, including video inputs and outputs is good for a monitor of this size, covering multiple DisplayPort 1,4 and HDMI 2.1 inputs, plus USB-C with power delivery and an audio jack. Ideally, we would have liked the ports not to all be positioned along the bottom for ease of access, but still. The monitor comes with built-in speakers, but as ever, these are of low quality.
OSD, features, settings & warranty
The OSD interface is organised in a relatively sensible way but the navigation controls aren't particularly intuitive, and you'll find yourself exiting the menu when you mean to select something, or going into a sub menu when you don't mean to, which does get annoying. You basically have to move the stick downwards rather than clicking it in to select/change any settings.
The GZ2711 comes with a fairly basic set of OLED care options: there's your classic pixel refresh/clean setting, a screen shift setting that's solely on/off with no levels to it, plus an on/off setting from ‘logo luminance adjustment'. Automatic Brightness Limiter (ABL) is activated at all times in SDR mode, with no way to disable it, which means the peak brightness is capped and will fluctuate at times, though this isn't uncommon in OLED displays. The monitor does have a KVM switch, although the official specs do not list it for some reason, which is good for productivity users.
The display is fully compatible with FreeSync Premium to help minimize screen tearing, though it only has G-Sync support, not full G-Sync compatibility.
The monitor comes with a 3 year warranty, which appears pretty solid at first glance and what you'd expect, however, upon further digging into the small print on the warranty page there's no mention of OLED burn-in cover at all, which is pretty standard for most new OLED displays, so this is less than ideal.
Screen testing & performance
We put the GZ2711 through all of our usual technical tests for color accuracy, brightness, and panel uniformity. You can seen the results below.
Color gamut
We recorded a gamut coverage of 99.5% for the sRGB space, which is effectively 100% for all intents and purposes, plus a 94.9% DCI-P3 coverage and an 88.3% Adobe RGB coverage – we wouldn't recommend trying to do any color-accurate work in these latter two spaces.
Color accuracy, contrast, gamma & brightness
Below are the results we recorded for the different presets we tested that are available within the monitor's settings menu. We tested for white point, black point, contrast ratio, average deltaE*00 (a measure of color accuracy), gamma, and brightness. In the top row, we've listed what is considered the ideal value for each of these data points, though to an extent this is jsut from a technical standpoint: the preset you actually prefer ultimately depends on your subjective preference and what you happen to be viewing on the monitor.
| Preset | White | Black | Contrast | Average deltaE*00 | Gamma | Brightness |
|---|---|---|---|---|---|---|
| IDEAL | 6500K | 0/m² | infinity:1 | 0 | 2.2 | 120cd/m2 |
| Standard | 6519K | 0.0 cd/m² | infinity:1 | 2.63 | 2.15 | 193.39cd/m2 |
| FPS Game | 6516K | 0.0 cd/m² | infinity:1 | 3.39 | 2.15 | 195.47cd/m2 |
| Movie | 7059K | 0.0 cd/m² | infinity:1 | 3.05 | 2.14 | 195.71cd/m2 |
| Web | 6529K | 0.0 cd/m² | infinity:1 | 2.63 | 2.14 | 197.14cd/m2 |
The best result overall was in ‘Standard' mode, followed very closely by the ‘Web' preset. The deltaE*00 score wasn't great across any of these, with none of them getting below 2.5, though both ‘Standard' and ‘Web' got close. Contrast and black point were as perfect as you'd expect on an OLED screen. Gamma was reasonable and the white point for ‘Standard', ‘FPS Game', and ‘Web' were all very good. SDR peak brightness peaked at 197.14cd/m2 in Web mode, but brightness does have a tendency to fluctuate downward thanks to ABL.
In SDR mode the lowest 0% brightness we recorded was 4.76cd/m² and the brightness setting which most closely equates to 120cd/m² (the approximate value for natural light) was 62%.
Once you enabled HDR mode (‘HDR10' in the OSD) it becomes very apparent that the color situation becomes a lot worse, with the screen appearing washed out. The peak HDR brightness when showing 10% of the screen (the standard we use when measuring HDR brightness) capped out at around 664cd/m2, which is not particularly impressive. All told, this is not a display we'd recommend using in HDR mode.
Panel uniformity
Panel uniformity shows how consistent the luminance and colors are across the whole screen. The display is split into a 5×5 grid, the central square being the reference point from which every other square is tested for variance. A variance below 1.00 shows up as green, which is the ideal result, being imperceptible to the naked eye. Yellow represents a greater degree of variation between 1.00 – 3.00, though at the lower end of this range this is still unlikely to be discernible to the untrained eye, and doesn't necessarily preclude the display from color accurate work. Greater variance is more of a problem, and shows up as red.
Looking at the results above, the majority of the display showed a variance below 1.00, which is a good result. The bottom row was an exception to this, with an average variance ranging between 1.05-1.49, however, this is still acceptable for color-accurate work outside of the professional space. It’s certainly good enough for gaming.
It should be noted that when it comes to panel uniformity, it can be a bit of a lottery, with different units having some variation between each other; however, this should be a decent approximation as to what most people can expect.
Viewing angles
As you'd expect from a WOLED panel, the Tempest GZ2711 has top-notch viewing angles, with very little detectable color shift to the naked eye when you view the screen from the sides, right up until you approach the 180° mark.
Gaming performance
We tried out the Cooler Master GZ2711 across our usual range of games, which includes CS2, Doom Eternal, Assassin's Creed Valhalla, and Cyberpunk 2077.
From a color vibrancy and immersion point of view, the monitor was solid, though it lacked the pop and vibrancy you'd get on a glossy panel. The contrast was as excellent as you'd expect though, and loss of color was minimal in both very dark and very bright scenes.
In terms of its speed in competitive shooters and the like though, the display was very good indeed when playing on its maximum 240Hz refresh rate. As you'd expect from an OLED screen, the 0.03ms response time was exceptional, and the screen met the claims of the manufacturer in this regard. Motion clarity at the native 240Hz refresh rate was great, with ghosting being barely perceptible in ‘real-world' gaming scenarios and during the Alien UFO test. FreeSync Premium also does a great job of removing screen-tearing and we noticed none during our playtime.
General performance & productivity
The Cooler Master Tempest GZ2711 is primarily a gaming monitor, although the KVM switch it comes with is a boon for productivity users if you want to switch between different PCs/other devices without changing your peripheral setup. The USB-C port with 96W Power Delivery is also very useful for connecting to mobile devices, tablets, or laptops and charging them at the same time.
Text clarity isn't great on this display – although the text fringing isn't any worse than on any other WOLED, the matte screen does also reduce clarity on top of this.
The peak brightness in SDR mode caps out at around the same point, which is standard for most WOLED panels (around the 200 nits mark), though the inability to disable ABL makes this slightly worse in this monitor. If you're working in a brightly lit environment, we probably wouldn't recommend this or any other WOLED monitor as a first choice for productivity.
On the ‘Standard' preset, color accuracy was the best, though it would only really be suitable for casual color-based productivity use, given the disappointingly high average deltaE score. The 99.5% sRGB gamut coverage is definitely sufficient for use in color-based workflows in the sRGB space, but professional visual artists and color graders will probably want to look elsewhere given the aforementioned accuracy.
Cooler Master GZ2711 OLED monitor
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