I have a very similar same problem: BSODs on entering Windows 7 after a cold boot with the same motherboard.
Typically, the BSOD occurs during bootup. The second bootup attempt is always successful.
CPU is an Intel Core i7 950. I have 6gb of RAM.
All drivers/firmware is up to date, and Prime95 indicates no stability problems. Do I seriously have to gut the system and return the board?
Gigabyte UK support basically told me "Search Google" - and I found this!