Desktop Effects (re-enable)
There are two ways to do this if you are using the fglrx driver.
1. Edit /etc/X11/xorg.conf file and remove
Section “Extensions”
Option “Composite” “Disable”
EndSection
OR
2. Go into the Configure your Comptuer -> Hardware – Configure Video card, Select graphic card, click Ok, click Yes and check the box
Enable Translucency (Composite extension)

Once you do that you should be able to login again and set KDE desktop effects from the Configure your Desktop icon.
Source: Desktop Effects
Advertisement