I have an Acer Aspire 4720Z. I was on the Internet last night when my screen blinked. About 20 minutes later my screen froze, so I turned it off. This morning I turned it on, and logged in. The screen is blank. I've tried turning it off and on with the same results. I don't want to reboot it because I've got some files that I need that are only on this laptop. Any suggestions? Please help!