This isn't going to be much help.
I've got the same board and sometimes it chooses not to give any display. The monitor shows the Bios POST information but when Windows changes to graphics mode, the monitor goes into stanby because it is no longer receiving a signal.
However, the machine IS running. If I use remote desktop from another computer, then I can see that everything else is running OK.
I wonder if it has more than one socket and it's choosing the wrong one? I'll have to have a look.