Tested with the latest upstream kernel, and the problem exists, (though I was able to get it once working after several LightDM restarts and HDMI cable attachs and disconnects).
Kernel's drm:intel errors have gone though. apt-cache policy linux-image-3.4.0-030400rc4-generic linux-image-3.4.0-030400rc4-generic: Installed: 3.4.0-030400rc4.201204230908 Candidate: 3.4.0-030400rc4.201204230908 Version table: *** 3.4.0-030400rc4.201204230908 0 100 /var/lib/dpkg/status ** Tags added: kernel-bug-exists-upstream -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/989226 Title: HDMI out doesn't work with ASUS Zenbook UX31E To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/989226/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs