Bad laptop video

I have installed 7.3 redhat on my DELL C600. Everything works great for all my
applications until I try using the alternate video port to send video to an infocus.

After that, everything screws up.

1. Have to use right and left mouse button to "grab" windows to move them.
2, My perfectly functional Java (1.3.1) application blows up (no error other than
abort).

Guess I'm looking for someone who knows these things well.
Anybody out there have experienced the same? Solved the
problem?

Thanks....

--
Wilbur R. Johnson
Distributed Decision Support Systems
Sandia National Laboratories