Yes, I was using the MB Bag! I just tried it on the MB box and had the exact same result. If the CPU was bad, would it have these results?
You probably shorted something out when you tried to start it on the bag. Definitely RMA the board, and in the future, test the mobo either on the box or a piece of wood or something else that's non conductive.
Those anti static bags really should come with a warning label. I see more people testing boards out and thinking it's safe to do it on the bag.
Yeah...I cringe every time I see a pic with someone testing on the bag. I sometimes use them when assembling if I don't have my ESD mat nearby but never powered up.