First let me say that I know zero about computers. When I first turn the computer on, it boots up but you can't see anything on the moniter. You can hear the windows music, but the keyboard and mouse won't work. Then the tower will turn itself off and on a few times. We go through this process a few times, and then finally it will work. I've been told it could be the video card or the power supply. Video card is a Gforce 7100 w/ DVI-I, VGA and S-video output. If that helps. Intel Processor is E2140. Any help is appreciated