Public bug reported: Using a Thinpad T420s, after upgrading to Ubuntu 16.04, I sometimes encounter a heavy problem:
The internal screen is frequently blanking and comes up with other resolutions. This mostly triggers after resuming from standby. Using xrandr, I figured out that there are too many display devices listed, and one of them, named VGA2, is intermittently thought to be connected, so it is automatically acitvated and the screen layout adapts, also changing the internal screen resolution (a clone view setup I guess). In reality, there are no devices, cables or adapters attached to any display output (there is only one VGA and one DisplayPort output). If bug kicks in, the computer is almost unusable, permanently switching the screen layout every few seconds. The bug cannot be undone by restarting Xorg and also holds after rebooting the machine. It can be fixed by power cycling the machine. ** Affects: xserver-xorg-video-intel (Ubuntu) Importance: Undecided Status: New ** Attachment added: "xrandr output" https://bugs.launchpad.net/bugs/1640781/+attachment/4775299/+files/xrandr.txt -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1640781 Title: Constant surplus display device detection and switching To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1640781/+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