X starting but nothing shows on the screen

["Ólafur Jens Sigurðsson" <ojsbug@gmail.com>]

Hello, I have a strange problem.

If X is started from gdm at bootup or with /etc/init.d/gdm start then
it starts (I know this since it beeps when it is up and running) but
nothing shows on the screen. The same thing happens when I use startx
and I have icewm in my .xinitrc. But if I have no .xinitrc file and I
use startx then Gnome comes up fine.

I am using sid and have just made an upgrade to my system (I hadn't
done a upgrade in quite a while and did an upgrade a few days ago then
my problems started) so it is up to date.

Any ideas on what could be wrong here?

Cheers, Óli