https://bugs.freedesktop.org/show_bug.cgi?id=27644
--- Comment #3 from Alex Deucher agd5f@yahoo.com 2010-04-14 12:32:57 PDT --- Please try dumping the registers when using kms and ums using avivotool as root: avivotool regs all > ums.regs avivotool regs all > kms.regs And attach the dumps here. Please specify what versions of xf86-video-ati and kernel you used to make the dumps. avivotool is part of radeontool: http://cgit.freedesktop.org/~airlied/radeontool