Well before you go running around and RMAing, you need to be totally sure that it's an issue with the part. Things get real easy since you have interchangeable parts.
I assume you already ran through our standard Won't post checklist? If not, here's the link.http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems
Run through that, see what turns up. It could be a number of things. Hard to say without more testing.