since a few days, X is eating almost all of the system’s resources. Usually getting as high as 60-80% CPU usage. I don’t know what’s with it, but nothing works against it, making it impossible to play any games while it’s funky. Is there something I could try against it?
What video card and what driver and what desktop. You are sure it is X that eats CPU? Did you look at top or system activity (ctrl-esc)
nVidia GeForce GT 320M, nvidia-gfxG03-kmp-desktop 340.96.k3.16.6_2-38.1, LXDE. When I open the desktop manager, it shows CPU usage.
the M in NVIDIA chip name indicates Mobil is this a optimus based laptop ie Intel+NVIDIA GPU??? If so you need either Bumblebee after removing the normal NVIDIA driver or follow instructions here.
If not a laptop then I don’t know check what was change recently in Yast-software management - extra - history maybe roll back anything that looks graphic related in the time frame where problem started.