We had a power failure last week, which shut the computer down. As a result, I was getting the message "auto adjust..." when turning on the computer. I fiddled with the button next to the on/off switch and that seemed to clear it up. Now the screen starts to get dark at the top and then goes black. Re-cycling the on/off makes it come back on but then repeats itself. This will go on for awhile then finally settles down. However it is annoying. Any hints/thoughts? TIA.