I have a toshiba Satellite M55 s3291 I have no experience with this stuff. But when i turn the machine on I never get to windows. The machine starts and the start up DOS like screen shows, Then the screen goes black. I can hit F2 or F12 to get to bios screen. So the screen does work, in color. I am guessing that maybe the windows OS has been corrupted. But I have no idea what to do next.