My pc was working fine until just one day the screen turned off showing the 'No Signal' sign. I checked and found that the video card has stopped spinning. According some of the things I've read online, removing the cd drive's connection could work and it did. But yesterday after shutting down to install updates, the video card doesn't spin anymore. And after rebooting the pc a couple of times, i found that my keyboard blinks on and off. What do you think is the problem? Is it the video card? Or the power supply?