What do you mean by "there is no proprietary driver available"? The nvidia driver in 11.10 should support it.
That said, I can try nouveau on my t420s, should be the same chip. ** Changed in: xserver-xorg-video-nouveau (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-nouveau in Ubuntu. https://bugs.launchpad.net/bugs/875309 Title: [Thinkpad T420] External video inoperative with Noveau To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-nouveau/+bug/875309/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp