Enable Compiz & Emerald with ATI
1. Install following packages, include all additional they request.
sudo apt-get install compizconfig-settings-manager emerald xserver-xgl
2. Enable ATI:s restricted drivers via System/Administration/Restricted Driver Manager.
3. Restart your system.
4. Right click desktop and choose Visual Effects/Custom.
Now it should have enabled Compiz and you can change settings via Preferences/Advanced Desktop Effects Settings.
Note: On some systems, like my laptop the settings for Emerald doesn’t get activated until i run Emerald with replace command, start by opening run(ALT+F2) and the write emerald ––replace and click Run and your settings should go through.

