Comment 17 for bug 1311316

Here as well, fresh install of 14.04 on a Dell Latitude notebook (Intel graphics) with the internal screen and two external screens being in use.
Happens randomly as it seems.
Only one time I didn't get password field but at least the cogwheel icon on the top right, so I could select "switch user".
But most of the time there are no user interaction elements whatsover.