[ubuntu] Graphics still to slow after adding 3D acceleration in Ubuntu 13.04 guest

I have installed an Ubuntu 13.04 Guest in an Ubuntu 13.04 Host machine.
At first the graphics were very slow. (By the way I have a discrete Nvidia graphics card).
Then I added 3D acceleration (see picture below).
Now the machine is just a little bit to slow.

What can I do to improve the graphics?

Unity 3D supported.png

Attached Images

• Unity 3D supported.png (12.8 KB)