Okay, what could this mean?

The Fn-F4 key doesn't work, at all. I have discovered that the VGA out works
great, but that's all that works. When I hit Fn-F4, the external display
will flicker, but not change. Furthermore, under the hardware list, I show 3
'standard displays'. The LCD doesn't appear on the list. Too weird.

So, LCD display works for text and the initial VGA only graphics modes for
OS installation, but goes out to the external display only, after loading
the ATI Radeon Mobility drivers provided by Compaq.

Bummer!