Hm, ok. Those logs indicate that the X server thinks it's successfully changing the mode, and there are no error messages visible anywhere.
That would indicate that this is likely a kernel bug. Could you please run ‘sudo xdiagnose’, tick the “extra graphics debug messages” box, hit ‘apply’, and then reboot? Once you've rebooted, could you reproduce the bug again and attach the output of “dmesg” here. That will have as much debugging data as possible! It would also be useful to try a newer kernel, as it's possible this has already been fixed - http://kernel.ubuntu.com/~kernel-ppa/mainline/drm- next/current/ contains builds of newer kernels. If this bug is fixed there then we've got a much easier job - just hunting down what change fixed it, rather than working out how to fix it :) -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/840865 Title: changing monitor resolution does not work To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/840865/+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
