Another peace for the puzzle: bug vanished until another reboot. After 13h I powered on the monitor and (surprise) there was a DP signal. I turned off 2 times waiting ~ some seconds and ~ 2 minutes. And for both I got the DP signal.
Then I rebooted, turn off and of the monitor and the bug is there again: _NO_ DP signal. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/927605 Title: Regression: monitor DP signal not turned on when monitor is switched on To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/927605/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs