Both the BSOD errors indicate a RAM problem. That's for sure. I also agree with apokalipse, in that ASUS boards can be very picky when it comes to RAM.
So try swopping it and see what happens.
Don't rely on memtest.
Athlon 64 3000 E6 Venice @2.43Ghz
Gigabyte 3D Rocket Cooler
ASRock 939 Dual SATA2 Bios 1.20
2x512mb Corsair VS @DDR348 1T
XFX 6800GT PCI-E @400/1100
Maxtor 120Gb SATA
Antec TruePower 550W