This took a lot of time to solve, but I’ve finally found the solution:
I’m running Kubuntu 8.04 on a HP nx9420 wich haves an ATI x1600 mobile graphics board.
I was never able to make the fglrx driver and xorg server to assume on boot up the fglrx driver. It always started with the mesa driver, which is OK but too slow for example Google Earth.
The solution on this case was after boot up, on KDE open a root shell and run the command: dpkg-reconfigure -phigh linux-restricted-modules-`uname -r` and then hit CTRL-BACKSPACE.
This was annoying because it means a long boot time until I had a stable system.
Then I installed the envy-ng wich installed the latest ATI drivers. Sundendly the compiz started to work, and everything looked fine, except the shutdown… it hangs with a black screen and the only way to recover was to press the power button for 5/8s.
It works right away. Thanks!