So I have gotten this laptop that would turn on every time I put in a little juice into it ie; battery, power cable. Now the confusing part is that when it does turn on the screen stays black. I've tried everything I can without changing the hardware (besides the HDD for testing) unplug, battery, holding on the power button, etc. It turned on fully once before, but as soon as i try to shut it down it stays on or shuts off then turns on again, yet it still doesn't show any sign of the screen turning on. I have also tried plugging in another screen. It worked and was the time it turned on. Both screens on so I imagine that the screen works fine. what do you think is wrong with this computer?