Secondary Monitor Glitching on KDE Wayland (open source Nvidia driver)
Hi everyone, I've neen having this issue when running KDE wayland with multiple screen on my Thinkpad W530. I'm using the nouveau driver.
The primary monitor is fine, but the secondary one is glitching.
This is tested on Gentoo as well as Debian. I know it's not hardware issue because it runs fine on X11.
Anyone have any idea about this issue?
Edit: I should probably mention that I was using DisplayPort in the photo, but I also tried VGA and it gave the same result.
Edit1: I was able to narrow down the problem somewhat. Switching the BIOS setting to "Discrete only" for the GPU (thanks coreboot!) seems to make the glitching go away! This means the Optimus would be to blame.
I have had the exact same issue and I've been looking for a solution. If you really need the second monitor then you can just switch to the x11 session as a temporary fix but I have no idea what actually causes it.
Could be an NVIDIA issue where the fact the external display is connected to the dGPU is causing issues. Nouveau optimus support(rather lack of it) for quattro could also be leading to the issue.
It's a common wayland problem. Try editing xf86config to force the scanrate to something your monitor supports rather than relying on dpms ddc/ci auto config