bought parts, got the rig running, bought a Win 7 COA key on ebay... it's a dell key, and it was blocked by Microsoft both online and by phone. I guess it's my mistake to think that Microsoft would let it go through so my question is: Can I successfully activate a legit key from any OEM source on this motherboard? Is it just a gamble if the key is going to be blocked? Or do I need a specific key that will work with MSI, or am I screwed by using MSI, do I need a retail key?