Public bug reported: Hi,
I'm using a Dell XPS 13 (9343 // i7-5600U broadwell, 3200x1800 panel) laptop, directly attached to an external Dell P2715Q 4K (3840x2160 @60Hz) via DP. The 4K external screen is flickering when doing light activity -- easily reproduced when using an X terminal. Steps to reproduce: - open side by side Firefox (or Chrome) + a terminal and/or a gvim window on the external 4K screen - do some light web browsing - give focus to the X terminal or gvim // at this point, display is still perfectly steady - press a key to enter a single character // as soon as the key is pressed, external screen goes black for a few seconds. Laptop screen is not affected. - Wait for the screen to come back, then continue typing // screen generally stays ON, but sometimes continues to flicker a few times in next minute. This happens almost every time I switch to the terminal window and start typing. OS specs: - Ubuntu 16.10 running Unity, modesetting Xorg driver - kernel 4.8.0. Issue is still present with 4.9.0rc1. The intel driver (cp /usr/share/doc/xserver-xorg-video-intel/xorg.conf /etc/X11) doesn't exhibit this issue. Also reported upstream: https://bugs.freedesktop.org/show_bug.cgi?id=97264 ** Affects: xorg-server (Ubuntu) Importance: Undecided Status: New -- 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/1636486 Title: External screen flickers (esp. in terminals) with xorg modesetting driver on Intel Broadwell To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1636486/+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
