Sony Vaio FX101 external monitor

Hi All,

	I wonder if any one can help with a problem I am having. I have
recently installed Red Hat 7.3 on a Sony Vaio PCG-FX101 with KDE everything
is working fine except I would like to use an external monitor with the
laptop. The usual way of switching to this (with the Fn key) doesn't seem to
work. Could anyone give me any advice on what the problem could be.

Thanks in Advance

Robert