https://bugzilla.kernel.org/show_bug.cgi?id=59101
--- Comment #5 from Cyril N. cx42net@gmail.com 2013-06-03 14:13:28 --- $> glxinfo | egrep -A2 "rendering|OpenGL"
direct rendering: Yes server glx vendor string: SGI server glx version string: 1.4 -- OpenGL vendor string: X.Org OpenGL renderer string: Gallium 0.4 on AMD CEDAR OpenGL version string: 2.1 Mesa 9.1 OpenGL shading language version string: 1.30 OpenGL extensions: GL_AMD_conservative_depth, GL_AMD_draw_buffers_blend, GL_AMD_seamless_cubemap_per_texture, GL_AMD_shader_stencil_export
And I uploaded my Xorg.0.log files.
I hope it'll help ! :)