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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.
The XG27AQWMG accepts HDR10 signals with an automatic switch and four specific picture modes. All can be adjusted for brightness and contrast with a toggle in the OSD. Tandem OLED technology means you get higher brightness than other screens and that rings true in my test results.
HDR Brightness and Contrast



The XG272-2K is exceptionally bright at over 930 nits for a 25% window, but the XG27AQWMG is the best of the rest by a significant margin at 653 nits peak. You can expect a 3% window to top 1,000 nits, which means small highlights will really pop. The HDR image here is exceptional, especially with variable brightness in play. The two AOCs at the bottom clearly highlight the difference that makes. Though they look solid in HDR mode, they don’t offer any more dynamics than SDR. The XG27AQWMG’s HDR is far more impactful.
Grayscale, EOTF and Color



Asus always does a solid job with HDR color tuning and the XG27AQWMG is no exception. Grayscale is a tad warm, but those errors can’t be seen in regular content. The EOTF tracks close to the reference, being slightly too dark below 40% and slightly too light above that. These are minor errors. The tone-map transition is at 70% brightness, which is correct for the measured black and white levels. I measured the other modes and found almost no difference between them.
In the color tests, the XG27AQWMG makes the most of its wide gamut with general oversaturation in all colors at all levels. Hue targets are in line, and the points progress in a linear fashion. This keeps all detail visible in all areas of the image. This is a textbook example of proper HDR tuning. In the BT.2020 test, the XG27AQWMG runs out of color at 90% red, 75% green, and 95% blue. This is excellent performance.
Test Takeaway: The XG27AQWMG is brighter than nearly every other OLED I’ve reviewed, and it takes full advantage of that ability in HDR mode. The picture is stunning, and though I’ve said that about most OLEDs, this one is just a little better. The fact that it’s also less expensive than its competitors makes a compelling argument for its purchase.
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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.