https://bugs.freedesktop.org/show_bug.cgi?id=56663
--- Comment #8 from dagg stompdagger1@yahoo.com --- (In reply to comment #6)
(In reply to comment #5)
I'm not sure, correct me if I'm wrong but Zaphod is for running seperate x sessions on the same card? I'm using a card per session.
anyway, I'll revert the patch and try, will report soon.
You are correct, but I'm wondering if that patch is causing a problem in your case. You might try reverting that patch as well if the 2D tiling patch doesn't help.
issue confirmed, it was indeed that Zaphod patch.