I changed the driver from 'ati' to 'vesa' in xorg.conf and there have been no freezes since (about one week ago). Therefore this is definitely a bug in the ATI driver. Unfortunately vesa is only a workaround, since there is no xv, 3D acceleration etc.
-- Switching between workspaces causes a hard freeze https://launchpad.net/bugs/54827 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
