if you haven't got a spare card to test the system with, i would recommend taking it to the nearest PC repair shop, which should have a different known good card to test on the system. a local PC repair technician would probably have a spare card as well.
XFX agreed to RMA the card. Got a 7300LE to use in the interim. Installed it two hours ago- have had two crashes since! The only difference is that Windows reporting now says it doesn't know what did it, as opposed to "thread stuck in device driver."
OK- guys- corrupt Windows install? Bad mobo/chipset? Just my luck? Have zipped up the last four minidumps, but I know they don't go here. Just looking for advice on where to look next.
you can try reinstalling windows if you want, but first i'd make sure all of your drivers are installed and up to date. a bad mobo could be causing this too. my advice is to back up your important files.
Just an update- replaced P5N-SLI with MSI P965 Neo- no crashes yet. After XFX sends the new 7900GT, I'll install it, and hopefully come back and close this thread.