bugzilla issue #17342 is Bug #23513 in launchpad which, oddly enough is the very bug I made that comment in. I have no idea why my comment has a link to the bug in it.
I do think this sounds like the same issue. Your find that susepend is simply not supported with this driver looks promising. I would mark this a duplicate but I'd prefer one of the ubuntu engineers have a look first. ** Changed in: xserver-xorg-video-ati (Ubuntu) Status: Unconfirmed => Confirmed -- X extremely slow after resume on ATI mobility M4 with DRI https://launchpad.net/bugs/56273 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs