Boot an alpha-2 livecd (http://cdimage.ubuntu.com/releases/12.04/alpha-2/) and assuming that works properly, collect the Xorg.0.log, xrandr --verbose, and dmesg from that, to compare with. It's odd that it doesn't show an LVDS output, I wonder if it did previously.
Also, just so I understand your report, are you trying to connect the external display to the VGA port or to the eDP port? ** Changed in: xserver-xorg-video-intel (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/946311 Title: only external screen is working with asus zenbook ux31e To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/946311/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs