When I try to attach an external monitor to my laptop, the windows are stretched oddly horizontally and the click offset is off. The nvidia settings also doesn't seem to show the built-in laptop display, but the ubuntu display settings does.
If I add a third monitor, the two external monitors work fine with no stretching or misclicking, but the laptop monitor is blank. I can't drag windows to it but I can move the mouse there.
If I use any monitor by itself, it works fine.
This is a fresh (with the exception of crashplan) install of 14.04.1 LTS x86_64, using the latest tested driver in additional drivers (nvidia-331.113 and nvidia-prime). It's on a Dell M6800 with a Quadro K4100M. Displays are connected via display port from dock.
Since I can't post images, here is an album of screenshots:
update: purging nvidia drivers and using Nouveau works fine, but runs slow.
update: It is related to Nvidia Optimus. Turning that off in the BIOS fixes the issue, though I'd like to be able to switch to my integrated graphics in the future.