I had successfully installed NVIDIA-Linux-x86_64-302.07.run from the nVidia website. That got me nothing but an unalterable 640x480 screen. purge and autoremove didn't seem to undo it.
I attempted, via Ubuntu Software Center, to reinstall nvidia-common(295.40-0ubuntu1.1), but that doesn't get me anywhere either. unity --reset doesn't help (Compiz errs).
Is there anything, short of wipe/reinstall of 12.04, that I could try?