Originally Posted by xificurk
@Zem: Do you use KDE4? If so, try switching between opengl and xrender backend for desktop effects. I've experienced a similar behaviour on my Vostro 3700, but it seems it went away after switching to xrender backend.
Thanks. Yes, I use KDE 4.
Switching to xrender has the same effect as disabling desktop effects, with regard to this problem; however, at least on my pc, xrender is considerably slower than opengl.
Maybe I should mention that I didn't have this problem on Kubuntu 10.04 on the same pc (I was using an older version of nvidia_bl). Maybe this is a problem with recent versions of nvidia drivers? I'm using the latest drivers from ubuntu-x-swat ppa.