I had to underclock the memory clock of my MSI 8800GT 512 OC-E because ArmA used to crash after 30 mins, resulting in red fragments all over the screen and then a BSOD.
The same on Hitman Blood Money but just in very rare cases, so I guess it's not ArmA's fault.
I know this card was a RTM case back when I bought it, but I was too lazy to change and I was fine with 900 MHz instead of 950 MHz, so...
Also neither temp nor power is lacking. I don't know which power supply I have because I'm kinda on the other side of the world right now but my cousin set up the rig for me and I told him I wanted a rig that could smoothly play Crysis with max details (ArmA didn't ring a bell for him so I had to give this embarrasing example. Oh btw, Crysis ultimately ran with about 15fps on max settings, but ArmA was fine (except for the red fragments of course)).
Also temperature is in green zone all the time. I check it with EVGA tools (forgot the name), since the newest version of Rivatuner wouldn't run on my x64 Vista (too lazy to turn off driver check crap ...). But anyway it's the same author and the same program.
Well, to come back to topic: Maybe the driver crash is because the card is just fubar
Gonna get a 285 GTX or something when I'm back home I guess (except ArmA2 will run fine on the current one, but I doubt it since it's the same engine).