The GC is a single core console. The Wii had 2 cores. To split those emulated cores up over more cores in the emulator would require a major overhaul to the emulator, and would not give any significant gains in speed.
So the only option is to just have a faster CPU. The FX-6xxx has really low per-core speeds, as I said earlier. Even with your overclock, it will still struggle in some games. Have you put your computer into high-performance mode under power management? Also, try using the OpenGL backend with the vertex streaming hack enabled.
So the only option is to just have a faster CPU. The FX-6xxx has really low per-core speeds, as I said earlier. Even with your overclock, it will still struggle in some games. Have you put your computer into high-performance mode under power management? Also, try using the OpenGL backend with the vertex streaming hack enabled.