I have tried to install the AMD Proprietary Driver by following this guide
http://wiki.cchtml.com/index.php/Ubuntu_Natty_Installation_Guide
but I guess I didn't succeed. In the standard Unity mode, the movement of the windows were really slow/laggy, but the 2D mode was working just fine.
Can anyone who succeed to use 11.10 with HD6950 help me? Which driver should I use and how should I install it?