We bought our Compaq a little over a year ago. The monitor was the display at the store. Now the monitor goes black! It starts with a strip of black "static" on the left-hand side of the screen, then it progresses to strips all the way across, and then it will go completely black. It is still on-\-not in sleep mode. It will flash back to the screen and then go black again. There is no common denominator when this starts to happen. HELP!