I have tried everything in the Performance Guide ( ) I even disabled EFB Copies altogether and everything else to boost speed and the most simple game I have (The Sims 1) still runs at most 70%, the second game in the series The Sims Bustin Out runs around 40%, while The Sims 3 for Wii runs at 100%. Dolphin seems to work perfectly with Wii emulation, they all run at 100%, but for some reason all Gamecube games are significantly slowed down, and despite adjustments to settings the speed is unaffected. I'd list comp specs but I already did at registration so I'm guessing you can see them.