I'm running an Alienware 14 (with Nvidia Optimus graphics). I've gone from 14.04 LTS to 15.04 to 15.10, and in the process it seems I've gone wrong with packages. My kernel stayed on 3.19.32, but I was able to fix that. After the upgrade, libgbm1 and xorg refuse to update. Using Synpatic Package Manager and instructing either of those packages to update, I get this:
It seems like removing xorg, ubuntu-desktop and the nvidia drivers would be bad - I can't get anything out of Nouveau. I'm a complete Linux newbie and thus far thanks to this forum and others I've had a lot of success finding answers to every issue, but this one seems big. Any feedback would be most appreciated.