I recently installed fedora KDE, to give KDE another go. It’s still my favorite DE by far, but it appears nvidia still struggles with it, even on wayland, I had much more input delay than GNOME.
I tried the usual method of forcing the full composition pipeline to prevent screen tearing, but then the input delay is too much.
Maybe this is more of a question about why this is happening? It has been a issue for a while now, and nothing I know of makes it possible to get rid of screen tearing and input delay at the same time with nvidia.
Another thing is that for some reason, increasing UI scale on wayland increased input delay significantly, but doing the same on XORG did not.
In many cases screen tearing on NVIDIA can be fixed by using the kernel parameter nvidia-drm.modeset=1. Have you tried that? You will have to edit the GRUB configuration. I don’t know how much experience you have but I know that Fedora’s GRUB is a little weird and I don’t use Fedora anymore so I can’t really tell you how to do it.
I also recommend building your own optimized kernel with TkG, if you are capable of doing so. It shaves off a significant amount of input lag compared to a stock kernel, irrelevant to the KDE issue.
I have indeed tried that kernel parameter. However, I am unable to get a GUI output once it’s set, so I have to change it back.
Hmm I have not heard of TkG, I’m gonna look more into it.