Wow! Nice system!. Updating the BIOS would not be a bad idea. If you can boot up in safe mode, check the Event Log for other indicators of the error. Check this Blue Screen of Death Survival Guide: Every Error Explained - Page 1 | Maximum PC
for help of BSOD's.
Where you upgrading or clean install? Where you installing the 64 bit version? It sounds like either a BIOS compatibility issue or a 64 bit driver issue. You could try installing the 32 bit version of Windows 7 RC when it is available or get it from torrent.