When I press the power button all led lights come on except the battery light. The laptop stays on for about 5 seconds and then shuts off. There is no display during the the 5 seconds; even the fans do not run. But when I press the power button and the F12 key (with or without the battery installed) the led lights come and the fans run. There is still no display and I can't power off the laptop unless I take the battery out.