Roadhog video issue

Hi there i have just replaced my power supply in my road hog as the old had been hit with a power serge.
while waiting for the new power supply to arrive we were using a standard ATX power supply and every thing was working fine.
anyways the problem is that the secondary screen (run of the on board video out put not the riser card) is not working any more it turns on and dose the normal no input then blank screen is there anything in bios you need to do or any other thoughts...
im about to refit old power supply to see if that helps