I spent years on this and couldn't solve it. Now I know what was the reason on my Nvidia GT 6600. This card has an additional main connector on the card. This was connected with the power supply, but in the connection was a plug where 1 cable was not fitted right. Therefore the card gets only power from PCI Bus. That is definitely a power supply problem. Either the additional power supply is not connected at all or fails. Can be easily measured with mains test equipment. Also is possible that the power supply is to weak (I have 450 Watts and that was good enough after i repaired the connection). The error is gone now.
In my case, this error occurred after installing the NVidia ForceWare driver Release 158 Version: 158.22 in Windows XP.
I have this problem with the NVidia driver 190.62 (released 17.08.2009) on a GeForce 9800 GTX. It only appears when I play certain games or view any large video files. Changing or updating the driver was no solution, so I thnk, it must be a hardware problem.
From a support forum: "I get this error pretty frequently if I overclock my 8800gtx beyond 620 core. I read that increasing pci-e voltage a bit in the bios can help with this. It didn't work for me. I think I got this error as i was undervolting by Q6600 from 1.3 to 1.2675. Since I've put my CPU vcore back to 1.3, the errors are gone."
Some support forums indicate that the problem was gone after a motherboard firmware upgraded. See EV100161
for an example.