AOC Agon Pro AG346UCD Ultra-wide OLED gaming monitor review: Maximum color and solid value

The AOC Agon Pro is a 34-inch WQHD 21:9 ultra-wide QD-OLED display with 175 Hz, adaptive sync, HDR, and wide gamut color.

AOC Agon Pro AG346UCD
(Image: © Tom's Hardware)

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Our HDR benchmarking uses Portrait Displays’ Calman software. To learn about our HDR testing, see our breakdown of how we test PC monitors.

When the AG346UCD receives an HDR10 signal, it enables two dedicated HDR picture modes. These should not be confused with the three HDR emulation modes available for SDR content. You get Display HDR and HDR 1000 Max. I’ll talk about the differences below.

HDR Brightness and Contrast

I measured the Display HDR and HDR 1000 Max modes and saw no difference in peak brightness. Both top out at 237 nits which is the same value I noted in SDR mode. There is no option for variable brightness which is what OLED monitors use to achieve brighter peak highlights. Black levels and contrast are still unmeasurable, so HDR looks very good but without the verve most other OLEDs have. This is the AG346UCD’s one real weakness. I verified these conclusions by measuring full field and 25% window patterns and got the same result every time.

Grayscale, EOTF and Color

I measured Display HDR and HDR 1000 Max and got very different EOTF curves. The charts above show Display HDR which is the default and best choice. The brighter grayscale steps are a tad warm but nothing that will harm actual content. The EOTF trace runs slightly dark up to the tone-map transition at 70%. Some shadow detail might be hard to see but since the progression is linear, there was no problem in the content I observed. I noted that the 1000 Max mode darkened the picture considerably due to a low luminance curve below the tone-map transition. It also made no difference in peak brightness.

The color chart shows some issues that should be addressed by AOC. Color saturation hits the mark up to around 60% where the points fall short of their targets. The DCI-P3 chart should be fully covered to the 100% perimeter, but it isn’t. Blue comes close but red and green are 10-15% shy. This means the brightest colors will be slightly muted in HDR content. Most material falls in the 40-60% range but the most vivid shades don’t quite render. The AG346UCD is fully capable of this gamut so I can only conclude that this is an unintended result. A firmware update would take care of this issue.

Test Takeaway: OLED monitors need a variable brightness option to render the best possible HDR and the AG346UCD currently lacks this feature. That means its HDR peak is no higher than SDR. I also noted the brightest primary colors were undersaturated. This showed in the tests and in my gaming sessions. The awesome OLED contrast and black levels are there, but color should have a bit more verve.

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Christian Eberle
Contributing Editor

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors. Christian began his obsession with tech when he built his first PC in 1991, a 286 running DOS 3.0 at a blazing 12MHz. In 2006, he undertook training from the Imaging Science Foundation in video calibration and testing and thus started a passion for precise imaging that persists to this day. He is also a professional musician with a degree from the New England Conservatory as a classical bassoonist which he used to good effect as a performer with the West Point Army Band from 1987 to 2013. He enjoys watching movies and listening to high-end audio in his custom-built home theater and can be seen riding trails near his home on a race-ready ICE VTX recumbent trike. Christian enjoys the endless summer in Florida where he lives with his wife and Chihuahua and plays with orchestras around the state.

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  • Deflott
    I bought this monitor for 590€ and im super happy with it, only thing I'm not used to is when i play game like kcd without brightness setting and there is night I can't see anything :/
    Reply
  • dave.rara66
    I'm sure it's a nice monitor, but for the same price you can buy the Dell Alienware AW3423DWF. While it's capped at 165Hz (hardly a noticeable decrease) it has great HDR performance and a better warranty.

    Not better as in longer, but better in that they will never make you send in a monitor for repair. They instead ship you a new replacement panel (no deposit required) and you just drop the defective one in the same box and send it back - all prepaid. Best warranty ever (3 years).
    Reply
  • Deflott
    dave.rara66 said:
    I'm sure it's a nice monitor, but for the same price you can buy the Dell Alienware AW3423DWF. While it's capped at 165Hz (hardly a noticeable decrease) it has great HDR performance and a better warranty.

    Not better as in longer, but better in that they will never make you send in a monitor for repair. They instead ship you a new replacement panel (no deposit required) and you just drop the defective one in the same box and send it back - all prepaid. Best warranty ever (3 years).
    I bought agon for 590€ while Alienware one you sent cheapest i could find for 786€
    Reply
  • dave.rara66
    Deflott said:
    I bought agon for 590€ while Alienware one you sent cheapest i could find for 786€
    I should have clarified that the prices I'm seeing are in the USA
    Reply