I have had similar experiences on my Asus F3F and gma950. The image displayed on external display is definitely messed up. The only fix I found was an explicit Xinerama configuration that enables both. I'll attach a sample for you. The bad side on that solution is that the vga output gets never disabled and you will have to restart X to get rid of it.
I'd call the problem a X.org bug. Some automatic setting perhaps fails. ** Attachment added: "Sample xorg.conf" http://librarian.launchpad.net/5437594/xorg.xineyri -- extra VGA output on laptop https://launchpad.net/bugs/76152 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
