On windows startup, and randomly during computer use, the screen will go black and Ill hear the sound of a device being connected and disconnected (not always alternating) for a few seconds and the the screen will come back on. I've checked my video card and it appears securely in its socket, and the cable is fully connected, so I'm not sure what could be causing the problem. Any idea what the cause could be, or how I could diagnose the problem? Edit: Found additional info by using the Event Viewer. Apparently when the screen goes black the Service Control Manager has anywhere from 3 - 10 events going on. Not sure why this causes the screen to go black, or why I hear a device disconnect/reconnect sound though.