It was a big surprise for me, but yes: if you want to e.g. connect
a video
projector to your Vista machine, you have to restart the
machine.
For a long time I thought it was only a Solaris issue. With some
laptops
you just need to restart your X server session (i.e.
logout/login).
Recently I have heard from one of my colleague, who was giving a
presentation
(on the last Wednesday) he was not able to use the projector at all
(he unfortunatelydid not try to restart his...