Freezes During BIOS

I've got a friends computer that I'm trying to fix, but can't seem to figure out the problem. It's a Compaq Presario S4020WM and when I turn it on it comes up to an HP screen and then it goes to a black screen with a flashing cursor and freezes. If I try to enter the BIOS setup it normally hangs before loading that screen. If it does get in to the BIOS setup it freezes if I try to do anything.

I've tried a different working power supply. I've tried removing the CMOS battery for an hour or so to reset the CMOS. I've tried using both sticks or ram as well as each stick individually and in both available slots. Nothing seems to work.

Any ideas would be appreciated.

Ryan