Hallo, i have the same problem under Xubuntu 14.04 and a brandnew HP Zbook 14.
At system boot my external vga screen was detected correctly and a few seconds after Xubuntu-XFCE-Login the external screen isn't available. At a few seconds i have seen the correct XFCE-desktop through the login process. Here is my syslog-entry if i plug out an plug in the external vga-monitor: [drm:intel_dp_aux_native_read] *ERROR* too many retries, giving up The problem affects obviosly to a programming bug. See here: https://bugs.freedesktop.org/attachment.cgi?id=93781 (Patch Intel i915). -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1300914 Title: External screen undetected after first plug Status in “linux” package in Ubuntu: Confirmed Bug description: On Ubuntu 14.04, the external screen plugged on VGA is detected and get activated correctly. However, if I unplug it and then replug it later, it is not detected anymore and the screen receives no signal. A way to get it back to work is to reboot or simply suspend the computer. Sorry but I have no idea of what package is handling that. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1300914/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp