Comment 21 for bug 813343

nvidia-common 1:0.2.35
nvidia-current 280.13-0ubuntu3
nvidia-settings 280.13-0ubuntu2
xorg 1:7.6+7ubuntu7
unity 4.16.0-0ubuntu2
unity-2d 4.8.0-0ubuntu
unity-common 4.16.0-0ubuntu2

Note: nvidia-settings was gone/not working for some reasons. So I had to reinstall it (apt-get install --reinstall nvidia-settings).

As of the last update, I can confirm that the problems are gone.
Nvidia-Settings is working under unity (3D) again.

I cannot say, if this is due to updates to unity (which occured some days ago) or xorg,.

But due to real performance issues (xorg takes a lot of cpu) I work with unity2d which is very fast and needs much more less graphics power than unity(3d).

Thanks all developers who had an eye on this.