The AOC CU34G2X is a great ultrawide gaming monitor. It has a 144Hz panel with Adaptive Sync support, so even though it's not officially certified by AMD nor NVIDIA for variable refresh rate (VRR) support, FreeSync and G-SYNC still both work on it. It has low input lag, and although it has a quick overall response time, there's visible black smearing, which is typical of VA panels. Speaking of which, it has a high native contrast ratio, but that means it has narrow viewing angles, so it's not ideal for co-op gaming. The 34 inch screen and 3440x1440 resolution help deliver an immersive gaming experience, and it has a fairly aggressive 1500R curve to bring the edges of the screen within your field of vision.
The AOC CU34G2X is a good overall monitor. It's great for gaming because it has a 144Hz refresh rate, FreeSync and G-SYNC compatibility, and low input lag, but there's visible black smearing. It's good for office use or content creators thanks to its large screen and good text clarity, but it has narrow viewing angles. Unfortunately, even though it has a good contrast ratio, it doesn't deliver a satisfying HDR experience because it doesn't get bright enough to make highlights pop.
The AOC CU34G2X is good for office use. The large 34 inch screen allows you to open multiple windows side-by-side, and it delivers clear text thanks to its high resolution. It's decent to use in a well-lit room, but it doesn't get bright enough to fight a ton of glare. Also, it has narrow viewing angles, so it's not ideal for sharing your screen with others.
The AOC CU34G2X is impressive for gaming. It has a high 144Hz refresh rate with G-SYNC and FreeSync compatibility that you can achieve over a DisplayPort connection. It has low input lag and a fairly quick response time, but like other VA panel monitors, there's noticeable black smearing. It's great for dark room gaming as it has high contrast, but it lacks a local dimming feature.
The AOC CU34G2X is good for watching multimedia content. The large screen provides an immersive viewing experience, and the 21:9 aspect ratio is good for watching movies. It has a high contrast to deliver fairly deep blacks, but there's no local dimming feature. It's not the best for sharing your screen with a friend as it has narrow viewing angles.
The AOC CU34G2X is very good for content creators. The large screen space makes it easy to see your entire video timeline without scrolling too much, and the 3440x1440 resolution helps deliver crisp images. It has decent ergonomics if you need to place the screen in an ideal position, but it has narrow viewing angles, making it harder to share the screen with a coworker or client.
The AOC CU34G2X is decent for HDR gaming. It has great gaming features like a 144Hz refresh rate, VRR support, and low input lag. It displays deep blacks due to its high contrast, but it doesn't have a local dimming feature. HDR content doesn't look too different from SDR because it has a limited color gamut and doesn't get bright enough to make highlights pop.
The AOC CU34G2X has a gamer-oriented design with black plastic and red accents throughout. It has a fairly aggressive curve to help bring the edges within your field of vision. The stand and the screen itself have large footprints, so you'll need a big desk to place the monitor on.
The back is mainly black with a few red accents. There's a cutout in the stand that serves as cable management.
The build quality is decent. It's made entirely out of solid plastic, and the stand feels stable when making ergonomic adjustments. However, the screen wobbles fairly easily on the stand, and the bottom bezel isn't properly attached to the screen throughout. The controls are really hard to press and even cause the screen to tilt a bit. Also, there are rubber grips at the bottom of the feet that come off easily.
The AOC CU34G2X 34 doesn't have a local dimming feature. The video is for reference only, so you can see how the backlight on this display performs and compare it to a similar product with local dimming.
The AOC CU34G2X has decent brightness. It's lower than the advertised 300 cd/m² and may not be enough to fight a ton of glare. We even measured the brightness before calibration and didn't reach the advertised brightness.
We measured the brightness after calibration in the 'Standard' Eco Mode with the Color Temperature set to 'User', and Brightness at its max.
The HDR brightness is disappointing. It doesn't get brighter than in SDR, and it's not enough to make highlights stand out the way the creator intended. We measured it in the 'Game' HDR Mode and the brightness was about the same with the 'Picture' and 'Movie' modes.
The AOC CU34G2X has narrow horizontal viewing angles. It's better than most VA panel monitors, so the edges of the screen won't look too washed out if you sit close, and the curved screen helps with this, too, but we don't factor it into the testing. It still may not good enough for sharing your screen with others, though.
Once again, the vertical viewing angles are disappointing. Although the colors don't shift much, there's still noticeable color washout, and the screen appears dimmer.
The AOC CU34G2X has excellent gray uniformity, but this can vary between units. Most of the screen looks fairly uniform, and there's almost no dirty screen effect in the center, which is great. Uniformity is better in near-dark scenes, but there's a bit of backlight bleed near the bottom.
The out-of-the-box accuracy is great. Most colors are only slightly inaccurate, but not enough for most people to tell, and the same can be said about the white balance. Color temperature is on the warm side, but it's still close to the 6500K target. Unfortunately, gamma doesn't follow the target curve well as most scenes are darker than they should be.
There's an sRGB mode, but it results in a less accurate image:
The accuracy after calibration is fantastic. Any remaining white balance and color inaccuracies are impossible to spot by the naked eye, and color temperature is extremely close to the 6500K target. Gamma is improved, but some dark and bright scenes are slightly over-brightened.
You can download our ICC profile calibration here. This is provided for reference only and shouldn't be used, as the calibration values vary per individual unit, even for the same model, due to manufacturing tolerances.
The AOC CU34G2X 34 has a decent HDR color gamut. It has impressive coverage of the commonly-used DCI P3 color space, but the wider Rec. 2020 is limited.
Our measurement of the DCI P3 coverage is likely lower than other reviewers due to how we measure it. We measure it by sending a Rec. 2020 signal, but unlike most reviewers, we limit the colors to the DCI P3 primaries. This results in a lower but arguably more accurate measurement.
The HDR color gamut is okay. It's a limited by the okay color gamut, and even has trouble displaying very dark colors despite its high contrast. It can't display really bright blues either, but that's typical of LED displays.
The AOC CU34G2X has no signs of temporary image retention after displaying a high-contrast static image, but this can vary between units.
Overdrive Setting | Response Time Chart | Response Time Tables | Motion Blur Photo |
Weak | Chart | Table | Photo |
Medium | Chart | Table | Photo |
Strong | Chart | Table | Photo |
The AOC CU34G2X has a great response time at its max refresh rate of 144Hz. Like most VA panel monitors, there's noticeable black smear due to the slower response time in darker transitions. We recommend using the 'Medium' Overdrive setting because it's quicker than 'Weak' and has a lot less overshoot than 'Strong'. If the black smear bothers you, the 'Strong' setting has a much quicker response time, so there's no black smear, but there's inverse ghosting due to the overshoot.
Overdrive Setting | Response Time Chart | Response Time Tables | Motion Blur Photo |
Weak | Chart | Table | Photo |
Medium | Chart | Table | Photo |
Strong | Chart | Table | Photo |
The response time at 60Hz is okay. Once again, there's smearing due to the slow response time in darker transitions. Like at its max refresh rate, we recommend using the 'Medium' Overdrive setting, so you won't need to change the setting if the frame rate of your game drops. The 'Strong' setting has way too much overshoot.
The AOC CU34G2X 34 has a black frame insertion feature to try to reduce persistence blur. However, it works within a narrow range, and you can't use it at the same time as VRR. Also, it creates noticeable image duplication. Keep in mind that the BFI scored is based on the flicker range and not the actual performance.
Although the AOC CU34G2X isn't officially certified by either FreeSync or G-SYNC, we confirmed it's compatible with both VRR technologies. Both work at the full range over a DisplayPort connection, while only FreeSync works over HDMI up to 100Hz.
The AOC CU34G2X 34 has extremely low input lag that doesn't significantly increase with VRR enabled. We didn't measure the 10-bit HDR input lag because the max refresh rate with a 10-bit signal is 60Hz over HDMI, and we don't have the tools necessary to measure HDR input lag over a DisplayPort connection.
The large 34 inch screen allows you to open multiple windows side-by-side without them being too cramped together.
You can use the USB-B upstream port to connect your peripherals to the USB ports on the AOC CU34G2X.
The AOC CU34G2X has a few extra features, including:
We tested the AOC CU34G2X 34", which is the only size available for this monitor. There's also the CU34G2, which seems to only be available in Europe, though we don't know for sure.
Model | Size | Resolution | Refresh Rate | VRR |
CU34G2 | 34" | 3440x1440 | 100Hz | FreeSync |
CU34G2X | 34" | 3440x1440 | 144Hz | Adaptive Sync |
If you have one that performs differently from ours, let us know, and we'll update the review. Keep in mind that some tests, like gray uniformity, can vary between units.
You can see the label for our unit here.
The AOC CU34G2X is a great gaming monitor that's versatile for other uses too. It's a low-cost option that offers good value, but unless you work in a dark environment, other affordable options get brighter, like the Gigabyte G34WQC.
See our recommendations for the best gaming monitors, the best ultrawide monitors, and the best budget monitors.
The AOC CU34G2X and the Gigabyte G34WQC are both great gaming monitors. They have similar features with the same panel type and max refresh rate. Even though the Gigabyte is certified by AMD to have native FreeSync support, FreeSync still works on the AOC, and G-SYNC works on both. The Gigabyte has a quicker response time, but black smear is visible on both. The Gigabyte is better to use in a well-lit room because it has better reflection handling and gets brighter. However, the AOC has four USB inputs, which the Gigabyte doesn't have, and its stand offers swivel adjustments.
The LG 34GN850-B and the AOC CU34G2X are both great gaming monitors with different panel types. The LG has an IPS panel with wider viewing angles, while the AOC has a VA panel with higher contrast. Motion looks much better on the LG because it has a quicker response time, and it doesn't have black smearing like on the AOC. The LG also gets much brighter, so it does a better job at fighting glare. If ergonomics are important to you, the AOC offers swivel adjustments, which the LG doesn't.
The Samsung Odyssey G5 LC34G55T and the AOC CU34G2X are both great gaming monitors. The Samsung has a higher 165Hz refresh rate compared to 144Hz on the AOC, and while the Samsung has native FreeSync support, which the AOC doesn't have, FreeSync still works on it. The Samsung is a bit better to use in a well-lit room because it has better reflection handling and gets a bit brighter. It also has a much higher contrast, but this can vary between units. On the other side, the AOC has many more ergonomics adjustments, as you can swivel it and adjust the height, which you can't do on the Samsung.
The ASUS TUF Gaming VG34VQL1B is a bit better gaming monitor than the AOC CU34G2X. The ASUS has significantly faster response times, but there's noticeable black smear on either due to their VA panels. The ASUS has a 165Hz panel compared to 144Hz on the AOC, and while the ASUS is certified by AMD, FreeSync and G-SYNC work on both. The ASUS also gets significantly brighter and has better reflection handling, so it's a better choice for well-lit rooms. However, the AOC has better ergonomics because it has a much wider swivel and tilt range.
The Acer Nitro XV340CK Pbmiipphzx and the AOC CU34G2X are both great ultrawide gaming monitors. They have different panels with pros and cons. While the Acer has an IPS panel with wide viewing angles and low contrast, the AOC has a VA panel with high contrast and narrow viewing angles. They each have a 144Hz refresh rate, but the Acer has native FreeSync support, and the AOC is FreeSync compatible. Motion looks smoother on the Acer because it has a quicker response time, too.
The Gigabyte M27Q and the AOC CU34G2X are very different monitors. The Gigabyte is a 27 inch monitor with a 16:9 aspect ratio, while the AOC is bigger at 34 inches and has a 21:9 aspect ratio for more screen space. They also have different panel types with unique characteristics; the Gigabyte has an IPS panel with wider viewing angles, and the AOC's VA panel has a higher contrast ratio. They each have a high refresh rate and VRR support for gaming, but motion looks smoother on the Gigabyte due to the quicker response time.