https://bugs.freedesktop.org/show_bug.cgi?id=35095
--- Comment #10 from Chris Rankin rankincj@googlemail.com 2011-05-15 05:06:36 PDT --- (In reply to comment #9)
Could you test the latest Mesa master branch? There are some new HiZ fixes.
At best, those HiZ fixes didn't help. But I suspect the corrupt area on the login screen may actually be larger now.