Asus ROG Swift PG27U 4K Gaming Monitor Review: $2,000 & Worth Every Penny

Grayscale, Gamma & Color

The PG27U includes a factory-certified calibration for its Racing image mode. We measured that, as well as the sRGB mode before calibrating the white point.

Grayscale Tracking

We describe our grayscale and gamma tests in detail here.

If you leave the PG27U at its default settings, it doesn’t require a calibration. The sRGB preset measured identically to Racing, so we didn’t include that chart. For us, grayscale tracking here ran ever-so-slightly blue from 70-100 percent. This is a barely visible error that few people will see apart from a test pattern.

Calibration produced pro-level performance with all but two brightness steps under 1dE (green horizontal line). It doesn’t get much better; this qualifies the PG27U for professional use.


A grayscale error of 3dE puts the PG27U right in the middle of the pack. This is average performance, even among premium gaming monitors. You won’t need to calibrate, but there is some room for improvement.

After calibrating to 200 nits brightness,, the PG27U was bested only by the LG 34WK650. However, an average error of .69dE is still among the lowest we’ve recorded for any monitor.

Gamma Response

The only gamma adjustments available are five accurately labeled presets. We stuck with 2.2 for our SDR tests.

As you can see, calibration made no difference here. The dip at 10 percent is not visible in actual content, nor does it affect color tracking. This is excellent performance.


Both the gamma value range and average gamma deviation tests were spoiled slightly by that dip at 10 percent, But we have no complaints. The PG27U tracked luminance almost perfectly in Racing and sRGB modes.

Color Gamut & Luminance

For SDR content, we measured the sRGB gamut. The PG27U covers over 90 percent of the DCI-P3 color gamut, but we left that to the HDR tests, which you’ll find on page five.

For details on our color gamut testing and volume calculations, click here.

There is little to see here except accurate color and luminance tracking. Saturation points were on-target, and luminance levels were neutral except for a slight rise in the blue primary. Our grayscale calibration took the measured error from an average of 1.78dE to .56dE. Again, this is pro-level performance and easily qualifies the PG27U for color-critical tasks.


We haven’t measured many professional monitors that can render color this accurately. The PG27U may be a gaming monitor but it can easily be used in a video post-production setting. Along with a super low .56dE average color error, it managed to cover just over 90 percent of DCI-P3. No displays we’ve reviewed can cover more (nor can any televisions we’re aware of currently).. As you’re about to see, this premium performance extends to HDR mode.

MORE: Best Gaming Monitors

MORE: How We Test Monitors

MORE: All Monitor Content