Hi there,

just want to share my experience with the R600 +/- the sb backend:

3.8.13 + BFS so far is the best performing and most stable & smooth kernel so far (with an Radeon HD 5850) and using it with wine + Unreal Tournament 3 (afaik also working with hyperz and/or llvm enabled/disabled), Unigine Heaven 3.0; performance seems to be a little better with compositing enabled (compiz-fusion 0.8*) but there some lag introduced with it; great and smooth performance with sb backend & hyperz disabled; worked fine with sb backend and hyperz + Half Life 2 beta

3.9.2 + BFS lots of stuttering/lag in the video - so bad that sound skips for several seconds and video isn't updated for several seconds/lags, hard locks after several minutes (UT3) or immediately when e.g. launching Unigine Heaven 3.0, the screen turns black, the fan keep spinning in a fast manner, no reboot via magic sysrq key possible; llvm or hyperz disabled/enabled doesn't seem to make a difference

3.10-rc2 (no BFS available yet) some less stuttering than with 3.9* but very annoying (with UT 3.0, no sound stuttering), stable - at least with UT3 on wine, haven't tried out Unigine Heaven 3.0 yet; currently tried with sb backend and llvm & hyperz disabled

several kernel releases before 3.8 it seems I got quite unlucky and each time it would hardlock immediately or after several seconds