I have similar problems with an ATI RADEON x700Pro (PCI xpress w/256 MB) and an ATI 9800Pro (AGP w/256MB). Machine is an Intel MB, P4 3.60GHz, 2 GB RAM, 2 SATA 160MB drives configured for RAID 0 and a stripe of 128k .
My problems are that the game GPFs or is rare cases ATI VPU recovers. These problems are not consistent with respect to time, sometimes a couple hours, sometimes days.
I believe my problems are related to memory corruption which is then written to disk, as I have seen MS set the checkdisk to run several times after the game blows up.
I find it hard to believe that this is a graphics related problem in the hardware as I play FarCry and Splinter Cell 3 at 1600 x 1200 with everything on high and AA at either 4x or 6x depending on the machine I am running on.
The graphics problems could be a result of XML being corrupted .... anyone else seen any XML corruption when this blows up? Anyone know if there is a bug in the MS XML parser that has a fix?