+ 0 Votes My first guess would be either a failing motherboard, wizard57m-cnet Moderator June 9, 2013 at 12:41am PST or maybe just a simple failing battery on the motherboard. Other possibilities could be a power supply unit going bad, or at least not providing enough power. Maybe first check the battery, that's a relatively easy inexpensive fix, then the power supply, then the motherboard. By the way, when you switch graphics to on-board, you need to be sure and enter BIOS setup and tell the system which graphics you are using. When switching back to the graphic card, you'll need to do the same.