Comment 36 for bug 363672

I got this issue last night on my PC. I got this in my logs:
Xorg.0.log:
(WW) Apr 07 21:48:49 NVIDIA(0): The NVIDIA X driver has encountered too many errors. Falling
(WW) Apr 07 21:48:49 NVIDIA(0): back to write-back cached memory.
(EE) Logitech USB-PS/2 Optical Mouse: Read error: No such device

Syslog:
Apr 7 21:48:48 Lain kernel: [44952.795391] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.405094] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.428150] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.448307] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.474177] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.495281] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.517083] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008
Apr 7 21:48:48 Lain kernel: [44953.555508] NVRM: Xid (0005:00): 13, 0000 e0015f00 0000009f 00000308 000d0071 00000008

I left my computer around 21:30. Usually, I leave xscreensaver running to lock my system, but as I was re-encoding some files, I didn't activate it (in fact, I disabled it). When no screensaver runs, X would enable DPMS after 900 seconds (that's 15 minutes). Taken into account that the system was running, I'd have to guess that this problem occurred within 4 minutes after DPMS activation. This is also the first time I encounter this problem on my PC. X was taking all the CPU, messing up pulseaudio that was playing a stream from Audacious.
Also, both the keyboard and mouse did not respond to any input. Trying to change the LED for numlock and capslock failed. I had to SSH to the system and shut it down from there.

The system I'm using has a GeForce 7800 GTX with 256 MB of VRAM. Since it's a PC, there is no shared memory. I'm running Jaunty with Xfce4. nVidia driver 195.36.15 from the nVidia VDPAU PPA.

Aside from this nVidia issue, I've had the same kind of issue with my laptop that uses an Intel graphics card running Ubuntu Karmic with Xfce4. I would lock the system using xscreensaver and when it turns off the monitor, there is a fairly big chance it won't respond to anything and I have to force a power down or SSH to it and try to fix it that way. Sending the system to suspend or hibernate usually fixes it and allows me to resume work. I don't have any logs of that unfortunately. When I get the problem again, I will gather the logs for it too, so it can be compared to this issue, it might be related.