When you look on the back of the computer is there another set of
video out ports (vga or otherwise)? Mine has one that came with the
motherboard (ATI), but it was next to useless so I bought a separate
Nvidia graphics card with 512 MBs. I have never tried to shut the ATI
off in the BIOS, because it has not been a problem for me. It is
something to look into, just to see if it would work.