https://bugs.freedesktop.org/show_bug.cgi?id=35988
--- Comment #3 from madbiologist s.j.turner@uqconnect.net 2011-04-05 06:49:16 PDT --- Xavier - do the dynamic or profile-based power management settings work for you? This bug is about those settings not working.
If I understand things correctly, a hot GPU is to be expected when using the open-source driver without these settings.