do you mean render the graphics with the best speed or just render the best graphics? the emulator is still under development. don't expect your games to run perfect. the best revision out there is probably r4631 for some games. every computer performs differently on the many revisions out there. Just because someone can emulate a game perfectly on one revision doesn't mean it'll do the same for you. so I can't help you there. For me, the revision that works best for me is the one I posted up on here: http://forums.dolphin-emu.org/thread-5382.html
I tried revisions r4631 through r4636 and non of them seem to out perform my revision. Try out different revisions and see which one is best for your system. its a matter of trial and error. r4616 & r4617 have the best speeds while r4631 and above have the best graphics. try messing around with the plugins and try swapping the files inbetween these revisions and see what plugins work best for your system. also note that just because a new revision is released does make it better then its previous revision. Between d3d9 and Opengl though.... Opengl renders a game much better (visually) but its much much slower compared to d3d9. If you decide to use d3d9, d3d9 renders the graphics depending on the quality of your video card but in most cases the games runs with a much better speed. I usually get 50-115% with d3d9 enabled in my games and about 20-30% with Opengl enabled
I tried revisions r4631 through r4636 and non of them seem to out perform my revision. Try out different revisions and see which one is best for your system. its a matter of trial and error. r4616 & r4617 have the best speeds while r4631 and above have the best graphics. try messing around with the plugins and try swapping the files inbetween these revisions and see what plugins work best for your system. also note that just because a new revision is released does make it better then its previous revision. Between d3d9 and Opengl though.... Opengl renders a game much better (visually) but its much much slower compared to d3d9. If you decide to use d3d9, d3d9 renders the graphics depending on the quality of your video card but in most cases the games runs with a much better speed. I usually get 50-115% with d3d9 enabled in my games and about 20-30% with Opengl enabled