When I first turn it on it starts up and then the screen starts flashing in and out and then goes black. Checked power supply and it's fine. Any ideas??

Thanks. I can,but now I have a different problem. My wife decided to just buy a new one so I had someone remove the hardrive to retrieve her files. SInce then I started it bac up and it doesn't flash, but it ran a scan disc check and now the dektop background changed and after a few minutes the mouse freezes. Got any idea for this one???
Thanks again.Mike
