I had purchased an HP Pavilion with the unsupported graphics card Radeon HD 6470M. I chose to not install the ATI proprietary drivers and simply work with the generic ones.
After my upgrade to 11.10 I noticed that after installing the ATI drivers (not the post-release ones, as apparently people have been having issues with Unity), my graphics card is working well. However, the Unity plugin was unchecked in Compiz. I have rechecked it but nothing has changed. No matter what I check or uncheck in compiz (like wobbly windows), there is no visual effect (these effects all worked with the generic drivers). Even my desktops are in the a straight line format and not in the 2x2 orientation, which gives problems when I press Super+S.
Is there something I need to do to activate Unity again? Should I reset it? Any other advice will be appreciated.