i have the 6A code to. no bios bootup, no screen.

what i found out:
when i remove the cpu cooler and then start my system, it boots on the first or second time. later on the runnig cpu, i hookt the cooler on. i was able to install win7. but everytime i start the pc with mounted cooler, it wont boot and show me the 6A.
i updatet the bios to F4 and disabled "ratio change in OS". but this dident help!

i watercool my i7 3930k with the XSPC Raystorm. does anybody else use this block? maybe there ist some magnetic radiation going out of this pice and interferes with the mb?