To learn about our HDR testing, see our breakdown of how we test PC monitors.
The AW2521H accepts HDR10 signals without issue, switching modes automatically. There are no additional image presets for HDR, but you can adjust contrast and the RGB sliders.
HDR Brightness and Contrast
The AW2521H easily exceeds the DisplayHDR 400 spec with over 462 nits max brightness. And it falls into the category of monitors with effective dynamic contrast, thanks to its variable backlight. That gives it an HDR black level only a tad above the Samsung’s and a superb 7,890.8:1 HDR contrast score. The PG259QN comes close but it gives away around 900 points.
Grayscale, EOTF & Color
We used the same RGB settings from SDR Custom Color mode to achieve excellent HDR grayscale tracking. A few tiny errors appear around 50%, but by the time the AW2521H transitions to tone-mapping at 55%, there are no visible issues. Our measurements show the transition starts a little early. It should be at 65% based on measured white and black levels, but this is not a visible error.
The AW2521H isn’t a DCI-P3 monitor but does a reasonable impression of one by pushing the primary color outside the sRGB gamut a little. Saturation tracks linearly at the inner targets with most colors showing over-saturation. Although you lose a little accuracy, this helps HDR content look more vibrant.