Screen shuts off

I just got a new PC in from Newegg. Turned it on for the first time an right after the Windows 7 logo my screen says "No Signal" and goes black, the PC is still running though, been going on for about....20ish minutes, is it just loading up for the first time or what?

Ok I can log onto Safe Mode just fine...but not normal.

Check your drivers. Also you may want to try taking the video card out, and then putting it back in to make sure that it's in the slot securely. Also try to reseat the RAM and see if that helps you out.