I've built a new machine:
Asus M4A785TD-V EVO
OCZ DDR3 PC3-12800 (2x 2GB)
AMD Athlon II X4 630 Box AM3
I tried memtest with hiren boot CD (tested only 3GB) and showed no error. Then I tried the built in RAM test from the Windows 7 CD (2 passes no errors). I also deleted with a 0 pass the hard drive. The error I get is this:
0x0000007e (0xFFFFFFFFFC0000005,0xFFFFF8000C1AB0F3,0xFFFFF880009A8498,0xFFFFF880009A7CF0)