the directx plugin (the only one that works with the gma's) does not work as well as open gl (from my experience) and your processor isnt going to give you the best speed.
Checkout my latest project ( it is a program that downloads and compiles dolphin on mac and linux now): http://code.google.com/p/dolphin-emu-downloader (It's unofficial and maintained by me, not the dolphin dev team)
