it seems that your issue is that your driver limit the virtual resolution to 1680x1680 and the settings you try to apply go over than, could you add Xorg.0.log to the bug? The limitation seems a driver one, g-c-c could still have a better error message but I'm not sure it can do a lot about the limitation
** Also affects: xorg (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/856312 Title: Cant set resolution with two monitors To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/856312/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp