Cinema display 20 inch

[David Ulrich <dulrichlinux@yahoo.fr>]

Hi,

Is there a special patch, or a config to do to xserver to run 1680x1050 
on a 20 inch cinema display?
I can not get more than 1280.

I'm running 2.4.27-powerpc-smp with a radeon 9700 Pro...

It's possible to use the dual head?

Thx

David