Yesterday when i tried turning on my desktop computer it refused to let me see it’s output and there was a blank monitor screen! :s
However, the computer was working fine, and all lights on keyboard were fine too. But none of the monitors worked that I tried connecting to it.
How it got fixed? well, just turned it off, removed the power cable from the socket for some time and then put it back in, tried again and voila! it was working! :)
Hope it helps.