recently bought a new acer aspire x5900 (it was a store display model, but i doubt that would be the cause of any of my problems) and it seems to keep crashing. It doesn't change the screen, in fact it just stops moving everything entirely. the mouse doesn't move or anything, and my only option is to turn it off at the wall which I hate doing. It's usually when I start it up, and I feel like I'm doing something wrong. Can anyone help?