ok i worked around this issue. first i removed fglrx from the disabled modules in /etc/default/linux-restricted-modules-common and then i installed fglrx sudo apt-get install xorg-driver-fglrx and edited the xorg.conf file.
i used this howto: https://help.ubuntu.com/community/BinaryDriverHowto/ATI -- Installer X server startup fails https://launchpad.net/bugs/62002 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
