Our HDR benchmarking uses Portrait Displays’ Calman software. To learn about our HDR testing, see our breakdown of how we test PC monitors.
The M27Q X supports HDR10 signals and switches modes automatically with no need for user intervention. Traditional picture adjustments are locked out, but a few new options appear if you want to tailor the look of the HDR image.
HDR Brightness and Contrast
The M27Q X is rated for 400 nits in HDR mode, but my sample topped 526 nits. That’s very bright, so highlight areas will pop nicely. Unfortunately, there’s no dynamic contrast here so the black level is also quite bright. HDR contrast is no higher than SDR. The picture looks a tad more saturated in some content, but it is mostly the same feel. The top Asus and Samsung screens vary the backlight to improve black levels, so their ratios are much higher.
Grayscale, EOTF and Color
The M27Q X’s HDR grayscale tracking is solid until the mid-point, where blue starts to diminish. The picture looks a bit warm but not too far off the mark. You can increase the Color Enhance slider in the HDR menu to add some blue, but red and green will also be increased. This helps some content look better. The EOTF tracks closely to spec except for the 0 and 5% steps, which are too light. Here is where dynamic contrast would be a benefit. HDR black levels are too high. Though shadow detail is plainly visible, it’s more a dark gray than true black.
HDR color saturation is very good, with reds a little past their targets. Only 100% red comes up short. Blue and green are almost exactly on their targets. The yellowish-white point pulls magenta and cyan off a little, but this is a minor error. The M27Q X’s HDR color is a little more accurate than most of the HDR monitors I’ve tested.