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The Exiled · 21.06.2022., 22:46

Sudeći prema Correcting HDMI Colour on nVidia and AMD GPUs članku, problem je tak jasno u šrot HDMI i DisplayPort standardima.

Citiraj:

When a monitor with a resolution and refresh rate in common with TVs (e.g. 1920 x 1080 @60Hz) is connected to an Nvidia GPU by HDMI or DVI-HDMI cable, the GPU may to treat the screen as an ‘HDTV’ rather than a monitor. This is also quite common when using DP, even though that’s a PC-only connection. You can see how the graphics driver categorises things for the Full HD resolution as that shared with a TV by opening the Nvidia Control Panel and navigating to ‘Display’ – ‘Change resolution’. It will usually be listed under ‘Ultra HD, HD, SD’ as ‘1080p, 1920 x 1080 (native)’ as shown below. This first resolution list in Nvidia Control Panel lists resolution and refresh rate combinations which are listed in the EDID of the monitor as ‘TV’ resolutions rather than ‘PC’ resolutions. But the problem is not simply that the resolution is listed in the wrong way, it’s the effect that this can have on the colour signal that is important. The GPU may send out a ‘Limited Range RGB 16-235’ colour signal by default rather than the optimal ‘Full Range RGB 0-255’ signal.

Citiraj:

Unlike when connecting a monitor to an Nvidia GPU using HDMI, connecting an AMD GPU via HDMI is usually less problematic when it comes to the colour signal. The image is not washed out and it looks very much as it should on most monitors. When using HDMI, the default behaviour of AMD GPUs may not be to use a ‘Limited Range RGB (16-235)’ signal like Nvidia GPUs, but rather to use a ‘YCbCr 444’ signal which is referred to by AMD as ‘YCbCr 4:4:4’. In our testing, the use of ‘YCbCr 4:4:4’ compared to ‘Full Range RGB (0-255)’ had a slightly more pronounced effect on white point, contrast and measured colour values on an AMD vs. Nvidia GPU. It is still nowhere near as pronounced as comparing Nvidia’s default ‘Limited Range’ signal with ‘Full Range’ on models which show clear ‘Limited Range’ issues.

Citiraj:

We’re happy to see that since this article was first published, Nvidia have added that drop-down ‘Dynamic range’ option to the driver.
AMD usually always handles the signal correctly as ‘Full Range RGB’ by default in their more recent drivers.

Isti šrot video standardi i popratno kablovinje su bili razlog hajke na "sfušane" Radeon drivere za RX 5700 seriju koja se onda izbjegavala, samo da bi se naposljetku ispostavilo da je do HDMI/DisplayPort pizdarija.