I bought and assembled a new PC:
Asus m4a785td-v EVO
AMD x4 620
OCZ Black Edition 2x 2GB
WD 500GB SATA
Windows 7 Ultimate 64-bit fresh install BSOD on boot. Formatted, reinstalled, BSOD on install. Ran memtest -> no errors. Ran Windows 7 install in safe mode. Installed, random BSOD on Windows 7 startup, even in safe mode. Updated BIOS. Ran the Windows 7 memtest (no error), booted after some tries and ran Prime95 blend test for 12 hours straight with no errors at all! When the PC has booted, Windows 7 runs as smooth as possible, I've been playing STALKER for 4 hours straight with not a single hiccup.
Using Blue Screen View I can see that every BSOD involves:
ntoskrnl.exe
Ran sfc/scannow as admin:
Windows Resource Protection found corrupt file but was unable to fix some of them.
What's going on?