https://bugs.freedesktop.org/show_bug.cgi?id=29066
--- Comment #4 from Marek Olšák maraeo@gmail.com 2010-07-15 19:04:32 PDT --- (In reply to comment #3)
Yes, I don't know if they are closer to RV350 or to RV370. One difference from those is that RS4xx have only two render output units, but that's irrelevant for the driver, right?
It should be.
Would it be important to try latest libdrm? Ubuntu 10.04 has only 2.4.18.
I can't tell for sure, though there are a few fixes since 2.4.18.