Hi. This also affects my system (1920x1080 and 1680x1050 display). Bootoption nomodeset did not make any difference. But with manual configured xorg.conf the problem was solved.
Therefor I added the following section and now it works. Section "Screen" Identifier "Default Screen" Monitor "MyScreen" SubSection "Display" Virtual 3600 1080 EndSubSection EndSection Regards Daniel -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/864505 Title: [Oneiric] Cannot setup dual monitor with AMD 5870 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/864505/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs