Was it an 8k cable? Are you on wayland?
I'm on Wayland and the cable is HDMI 2.1 ultra high speed, which means 8k. Xorg is already gone on Ubuntu 25.10.
The GPU and monitor combination has full 10-bit HDR in Windows. But in Linux it's stuck at 8bpp due to nVidia driver not having 10-bit RGB output.
alt Hacker News
I'm on Wayland and the cable is HDMI 2.1 ultra high speed, which means 8k. Xorg is already gone on Ubuntu 25.10.
The GPU and monitor combination has full 10-bit HDR in Windows. But in Linux it's stuck at 8bpp due to nVidia driver not having 10-bit RGB output.