Right,
[Stage 1] Go back into BIOS and default everything, boot back up and do a stress test (make sure thats stable). 5 runs of IBT on high should be enough for now.
[Stage 2] Then back into BIOS and change the RAM down to 1.5v and 1333mhz (ignore timings). Boot back up and stress again.
[Stage 3] If its stable, back into BIOS and change the multiplier up to 40. Boot and stress.
[Stage 4] If its still stable, multiplier up to 42. Boot and stress.
[Stage 5] If its still stable, multiplier up to 45. Boot and stress (On this stress test, keep an eye on your CPU voltage, ensuring it doesnt go above 1.4v).
If it BSOD on any, tell me what stage.
Report back when youve done that....and do each step with a screen shot.
Out of curiosity, what programs do you have for monitoring your stressing?