Looked at my girlfriend's computer last night. The computer boots but, I think after the windows loading screen the screen goes black and apparently I can't do anything. I looked at set up and boot sequence, ran a hard drive diagnostic which passed and was not sure what else to do. Setup had a quick boot option where compatibility issues could be bypassed, I tried it with that on and off. My best guess is either the hard drive is bad or windows install. I could not find her windows disk to try repairing the install if that is an option. It is a dell with a P4, 1GB Ram, two 160GB Hard drives, Dell. Looking for suggestions on what to do next. Thought about trying my hard drive in the system to see if its the hard drive and may try reformatting or reinstalling windows if a disc shows up. I'll probably pick up the tower tonight and bring it home to work on it.