I have this problem on Linux Mint 17.1 (Ubuntu 14.04 base) too on a Lenovo T420s with Optimus graphics using the Nvidia card as primary.
It seems to work as expected if I put the screens in order [LVDS-1-0] -- [VGA-1-0] -- [DP-3] from left to right, but if I put DP-3 in the middle, I can't disable panning for it. Just putting the screens in this physical order works for me, but I run into another problem when I try to set the middle screen (VGA-1-0) to primary in order to get my KDE taskbar on the middle screen. Trying to set any of the screens provided by modesetting to primary fails with the following error: $ xrandr --output VGA-1-0 --primary X Error of failed request: BadMatch (invalid parameter attributes) Major opcode of failed request: 140 (RANDR) Minor opcode of failed request: 30 (RRSetOutputPrimary) Serial number of failed request: 50 Current serial number in output stream: 52 $ xrandr --output LVDS-1-0 --primary X Error of failed request: BadMatch (invalid parameter attributes) Major opcode of failed request: 140 (RANDR) Minor opcode of failed request: 30 (RRSetOutputPrimary) Serial number of failed request: 50 Current serial number in output stream: 52 I attach my Xorg configuration (generated by nvidia-settings), the Xorg log file, a dump of 'xrandr --verbose' output and 'xrandr --listproviders' output. ** Attachment added: "nvidia_multiscreen_problem.tar.gz" https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1326688/+attachment/4762455/+files/nvidia_multiscreen_problem.tar.gz -- 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/1326688 Title: Can't disable panning on multiple monitors To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1326688/+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
