I have compaq presario F700 notebook pc. Today I was transfering some files from a video cd to my computer when suddenly it hang up and the screen turned white I waited for some time but there was no change so I removed the batery and replaced ot back and started it again. Then I opened the files that I had transfered and after some time the screen went white again and I removed the battery again but this it refused to start. The power has light which comes and goes but the screen is black. what should I do?