Many thanks for testing, and sorry that I did only test in cooker (soon to be 2010.1)
I believe the difference in glxinfo output, as reported in
https://bugs.freedesktop.org/show_bug.cgi?id=28069 may be the actual cause. Cut&paste of small portion of diff with an ati card:
-direct rendering: Yes
+direct rendering: No (LIBGL_ALWAYS_INDIRECT set)
-OpenGL version string: 1.5 Mesa 7.8.1
+OpenGL version string: 1.4 (1.5 Mesa 7.8.1)
The remaining are some GL features available only in one or the other model (but causing a lot of noisy in diff)
I think both cards are ok, probably an issue with Mesa 7.8.1 branch. Well I am reporting the problem both here and in freedesktop, as I don't know by myself how to correct it or what is wrong, just found out that setting LIBGL_ALWAYS_INDIRECT makes difference (and changed the rpm package to do so for now
![Smile :-)](./images/smilies/icon_smile.gif)