I decided to upgrade both my computers from Precise to Quantal. What a mistake that was.

My laptop has a nVidia GT 330M card, while the desktop has an nVidia 9600 GT. In both cases everything goes great as long as I use the Nouveau driver (ugh!). Can't really play games (Amnesia... and hoping for Steam Beta participation...), even though it's OK for work.

Now, ever since 9.04 or so, I just installed nvidia-current and all just worked. Since 12.10, after installing nVidia drivers, Unity won't start at all (hangs with only the wallpaper displayed, no cursor or widgets), Gnome Shell is permanently in fallback mode.

Now, I have tried on both computers, with multiple clean installs on Ubuntu (two separate downloads, just in case), one from Ubuntu Gnome Remix. And additionally, Fedora 17, which seems to suffer from the same issue. Tried all nVidia driver suggestions available in Software Sources, and even compiled the drivers myself. I tried several versions of the driver to exclude an issue with the newest one.

In my frustration, I have switched to Windows (which, ironically, "just works" with my hardware), but still hold a twin OS configuration on the desktop and would like to use Ubuntu again. So, can anyone point me to where the issue might lie?