NVIDIA freezes my X (except mouse...)

Dear list, I tried to change driver in x.org from nv to nvidia. Since I don't have the suse-script in my online update that's how I did it: init 3 NVIDIA..pck1.run (said something about unknown kernel, building it from source..., install, update xorg.conf) init 5 Works great but only for a few minutes. If I start sax or nvtv it freezes immediatly just surfing with firefox I have some time before I have to do a cold start. X / KDE is frozen only the mouse is still working. What to do? Who managed to get NVIDIA to work? Is it somehow related to "tainted" flag in kernel? Thanks for help.