I've just started getting this same problem about a week ago, BSOD every few hours or so, often while it is idling. I just re-formatted and it is still doing it.

abit kx7-333r
athlon 1800
512 kingston
radeon 8500le

I've installed no new hardware or software, it just started doing it one day. i ran memtest86 overnight, and no errors.

at first it was giving me win32k.sys errors. then once it said hptpro.sys, my raid driver...so i took the hd off of the raid ide, and put it on the normal one, reformatted, and no success.

when i run chkdsk i get this message:
CHKDSK discovered free space marked as allocated in the
master file table (MFT) bitmap.
CHKDSK discovered free space marked as allocated in the volume bitmap.
Windows found problems with the file system.
Run CHKDSK with the /F (fix) option to correct these.

so i run chkdsk/f, reboot, and doesn't help. i also tried disabling my virtual memory, reboot, then enable to no avail...i'm convinced it's hardware, but what hardware? page fault...it could be memory or virtual memory no? or something else acting up?

HELP!