Infinite loop with Nvidia card

Hi,

I bought a ST6-RAID several months ago and I've been plagued with
infinite loop errors since then. I get a blue screen mentioning that
the video card driver (nv4_disp.dll) got stuck in an infinite loop.
I've tried everything from switching slots for my sound card and
network adapter, to playing with BIOS settings, changing the PSU and
even flashing to other BIOS versions. Nothing works! I keep
experiencing random crashes. Strangely enough, it only happens while
I'm on the Internet. This is driving me nuts! I know for sure that
it's not a temperature issue, because I've checked and my video card
is always cool. Besides I had previously added a thermaltake
fan/heatsinks combo on it. I know from other threads that I've read
that there seems to be a compatibility issue with that board when
using either a Soundblaster Live! 5.1 or Audigy, which caused random
reboots, and I have a Audigy. However, I don't know how that and a
BSOD about my video card could be related. I've also tried a different
video card in my system and my video card in another system and there
were no error on either side! It looks like the video card and the
board don't go well together. Has anyone else experienced this
problem? Lastly, I don't even use RAID and the RAID controller is not
enabled. Any help would be GREATLY appreciated. Here are my system
specs:

Abit ST6-RAID (BIOS v8A)
PIII Tualatin 1.13 GHz
512 Mb RAM (2x256 Kingston CL2)
Soundblaster Audigy
Nvidia GeForce 4 Ti-4200 64Mb, with AGP 8X (Drivers: ForceWare 56.72)
Linksys 10/100 LNE Fast Ethernet
WD Caviar 80Gb @7200, 8Mb hard drive
52x LG CD-ROM
52x LG CDR-W/DVD combo
Alpha 300W PSU