No video signal in the monitor. Also there is no signal going to the printer. What might be the problem. Power supply excluded. Already checked.

no power or no video? no video i'd check the cable first, then possbily the video card. if there's nothing on your display how are you sending a command to your printer? printer could also be a cable, but if you're having 2 issues with 2 separate devies, the common demoninator would be a likely cause. 

did any event occur leading to this issue? crash, fall, liquid spill, sw/hw change, etc?