I believe I have the same symptoms. I do not have the error in my Xorg log as Tony did.
Additional information: 1- error message dialog box pops up at startup: "could not apply the stored configuration for monitors.... none of the selected modes were compatible with the possible modes" 2- the font in my "home folder" is small/looks funny and all the graphics buttons are missing 3- running "displays" shows unknown display of the correct size of my two monitors together, pressing detect displays does nothing in X, but if started from a terminal: (gnome-control-center:2898): GnomeDesktop-CRITICAL **: gnome_rr_mode_get_id: assertion `mode != NULL' failed (gnome-control-center:2898): GnomeDesktop-CRITICAL **: gnome_rr_mode_get_width: assertion `mode != NULL' failed (gnome-control-center:2898): GnomeDesktop-CRITICAL **: gnome_rr_mode_get_height: assertion `mode != NULL' failed (gnome-control-center:2898): GnomeDesktop-CRITICAL **: gnome_rr_mode_get_freq: assertion `mode != NULL' failed 4- I was using Ubuntu 11.04 a week ago, didn't have this problem. This problem started after I installed 11.10 and enabled twinview 5- :/var/log$ xrandr -q xrandr: Failed to get size of gamma for output default Screen 0: minimum 3840 x 1200, current 3840 x 1200, maximum 3840 x 1200 default connected 3840x1200+0+0 0mm x 0mm 3840x1200 50.0* 6- Xorg.0.log file attached can you offer help? thanks, Brian ** Attachment added: "brian-Xorg.0.log" https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/859836/+attachment/2548418/+files/brian-Xorg.0.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/859836 Title: Monitors are not identified in Oneiric with radeon driver To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/859836/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
