Copy the following command into the terminal application in your Utilities folder:

sudo defaults write /Library/Preferences/com.apple.windowserver \Quartz2DExtremeEnabled -boolean YES

Then hit return, you will be asked for your passsword.Enter it & hit return again.

To deactivate, copy the following into terminal & hit return, you will be asked for your password. Enter it & hit rerturn again.

sudo defaults write /Library/Preferences/com.apple.windowserver \Quartz2DExtremeEnabled -boolean NO

Note: 2D Extreme can help speed up your computer if you have a powerfull graphics card by taking some of the desktop rendering duties away from the processor.