Flickering screen with GeForce 8500 GT, 185.18.14 driver, x86_64 double core AMD
I have severe problems with the 185.18.14 driver on an x86_64 double core AMD system with Ubuntu 9.04, kernel 2.6.28, GNOME 2.26 and a running compiz.
Sometimes some minutes after boot, sometimes after some hours of work the active window doesn't react on input weather by keyboard or mouse. Seconds after that the mouse pointer is "frozen" on the desktop.
After that the screen starts to flicker. The intensitiy of the flickering differs each time.
It is barely noticeable at some times, but it can also flicker very quickly.
In most cases I'm able to change via CTRL-F1 to a unix console. But this isn't everytime possible so that I have to reboot hard.
After changing back to X the background and sometimes the contents of the application windows are heavily garbled.
I read the forum entries about stability problems and tried the pci=nommconf option. That doesn't help much. The problem remains unpredictably. I could notice some pixel errors nearby the mouse a short time before the problem occured again.
I also tried idle=poll, and that helped for some time. But then the pc suddenly shut down after several hours of work several times in a row as if you cut electricity. So this doesn't really help either.
The problem still occures even if I deactivate the compiz window manager and use the normal window manager of GNOME without visual effects. It only takes more time.
If I use suspend to RAM the flickering seems to occure quicker than after normal boot.
I tried the available drivers from the archive but there was no real improvement.
Attached is a nvidia bug report of a logverbose 6 X-Server. I hope it can provide some clues for solving the problem.