X org keeps crashing after logging off

I've seen several threads that mention similar problems, but they haven't help fixed the problem. It's driving me nuts as I have to reboot the computer to switch user accounts, as Xorg crashes when logging off. I'm using ATI drivers with GDM.

Here is the output from lspci http://paste.pocoo.org/show/542226/
and the Linux Kernel config is http://paste.pocoo.org/show/542227/

Please post your thread in only one forum. Posting a single thread in the most relevant forum will make it easier for members to help you and will keep the discussion in one place. This thread is being closed because it is a duplicate of http://www.linuxquestions.org/questi...ng-off-926525/.