The Asus ROG Swift PG27UQ G-SYNC HDR Monitor Review: Gaming With All The Bells and Whistles

SDR Color Modes: sRGB and Wide Gamut

Pre-calibration/calibration steps of the monitor is done with SpectraCal’s CalMAN 5 suite. For contrast and brightness, the X-Rite i1DisplayPro colorimeter is used, but for the actual color accuracy readings we use the X-Rite i1Pro spectrophotometer. Pre-calibration measurements were done at 200 nits for sRGB and Wide Gamut with Gamma set to 2.2.

The PG27UQ comes with two color modes for SDR input: 'sRGB' and 'Wide Gamut.' Advertised as DCI-P3 coverage, the actual 'Wide Gamut' sits somewhere between DCI-P3 and BT.2020 HDR, which is right in line with minimum coverages required by DisplayHDR 1000 and UHD Premium. That being the case, the setting isn't directly calibrated to a color gamut, as opposed to sRGB.

Out-of-the-box, the monitor defaults to 8 bits per color, which can be changed in NVIDIA Control Panel. Either way, sRGB accuracy is very good, as the monitor comes factory-calibrated. To note, 10bpc for the PG27UQ is with dithering (8bpc+FRC).

SpectraCal CalMAN sRGB color space for PG27UQ, with out-of-the-box default 8bpc (top) and default with 10bpc (bottom)

In 8bpc or 10bpc, average delta E is around 1.5, which corresponds with the included factory calibration result of 1.62; for reference, for color accuracy a dE below 1.0 is generally imperceptible and a dE below 3.0 is considered accurate.

SpectraCal CalMAN DCI-P3 (above) and BT.2020 (below) color spaces for PG27UQ, on default settings with 10bpc and 'wide color gamut' enabled under SDR Input

The 'wide gamut' options are not mapped to either DCI-P3 or BT.2020, sitting somewhere in between, but then again, it doesn't need to be as a professional or prosumer monitor would.

Grayscale and Saturation

Looking at color accuracy more throughly, we look at greyscale and saturation readings with respect to the sRGB gamut. The dips in gamma aren't perfect, and the whitepoints are a little on the warm side.

SpectraCal CalMAN sRGB color space grayscales with out-of-the-box default 8bpc (top) and default with 10bpc (bottom)

The saturation numbers are better, and in fact the dE is around 1.5 to 1.4, which is impressive for a gaming monitor.

SpectraCal CalMAN sRGB color space saturation sweeps for PG27UQ, with out-of-the-box default 8bpc (top) and default with 10bpc (bottom)

Gretag Macbeth (GMB) and Color Comparator

The last color accuracy test is the most thorough, and again the PG27UQ shines with dE of 1.53 and 1.63

SpectraCal CalMAN sRGB color space GMB for PG27UQ, with out-of-the-box default 8bpc (top) and default with 10bpc (bottom)

Considering that this monitor was not designed for professional use, it's very calibrated out-of-the-box for gamers, and there's no strong concern for calibration. If anything, users should just be sure to select 10bpc in the NVIDIA Control Panel, but even then most games use 8bpc anyhow.

SpectraCal CalMAN sRGB relative color comparator graphs for PG27UQ, with out-of-the-box default 8bpc (top) and default with 10bpc (bottom). Each color column is split into halves; the top half is the PG27UQ's reproduction and the bottom half is the correct value