I've had an old IBM Thinkpad 560E for a number of years and it has always worked fine for the most part. A couple days ago I turned it on and nothing showed up on the LCD, no flickers, no faint picture nothing. I plugged it in to two known working monitors and no picture showed there either, no signal even though I know the monitors and cords work. I know the computer is on there are lights and I hear the hard drive and fans spinning normally and there are no beep codes on startup. What could be wrong?