Re: 9800GTX+ crashing, hardware or software?
Have you tried underclocking? I started underclocking mine about 2-3 weeks ago and it's been stable since then.
nvidia-settings -a GPUOverclockingState=1 -a GPU2DClockFreqs=225,828 \
The defaults for my card are 2D: 300,1000 and 3D: 745/1100.
I think it also needs:
Option "Coolbits" "1"
in the device section in xorg.conf.