Comment 6 for bug 1268184

The bug exists when only using nvida-331 and nouveau is blacklisted. Therefore I would expect the nvidia card to be the default and only card visible but it does not start.
It only starts if hd4000 is present (either because nvida-331 not installed or with bumblebee that manages both).
Bumblebee is not installed in the configuration the bug was reported against, though it can be installed w/o major issues, yet optirun fails when trying to address the nvidia card w/ bumblebee.
It doesn't look like a duplicate unless the laptop cannot start under nvidia for whatever reason and absolutely has to start under the hd4000 (wouldn't be normal).