Hello Michal and Mark, @Mark:
I don't know if this will help: Gnome tends to overrule your xrandr configuration (only in lenny, squeeze doesn't have this problem with the computer I've tried). Try disabling gnome xrandr plugin. To do this, go to gconf-editor, browse /apps/gnome-settings-daemon/plugins/xrandr and uncheck the "active" entry (Important, you will have to place a file with an appropiate xrandr initial configuration in /etc/X11/Xsession.d/ a sample is given in the link below). You could also try a simpler xorg.conf. Try NO options for the external monitor and set everything up in the xrandr conf file If you want more info, this helped me a great deal: http://www.jejik.com/articles/2008/10/setting_up_dual_monitors_system-wide_with_xrandr_on_debian_lenny/ @Michal: Is this still a problem with the newer radeon driver from squeeze? If so, could you try getting the even newer one from sid (you'll need a newer kernel as well, either 2.6.32-10 from sid or 2.6.33-1 from experimental). For this you will need to enable Kernel modesetting. add *radeon* to /etc/modules and put *options radeon modeset=1* in /etc/modprobe.d/radeon-kms.conf (you'll probably need to create the file). Let me know if these things work out for you guys. We need to help debian X clean up de RC bugs! Andres
