Is video not working on both front and rear VGA ports? Can you ensure control panel is connected properly? You can also check video in iDRAC?
After replacing a motherboard I can't get VGA signal on the crash cart monitor in order to apply the service tag to the new motherboard through the BIOS. I've checking connection and functionality of the crash cart itself. All checks out. I've even tried swapping out for a different new motherboard and the same issue persist. Thanks in advance. 
No VGA signal after swapping a motherboard r630