Dolphin, the GameCube and Wii emulator - Forums

Depends on the game. We can use many cores. One for the CPU, one for the GPU, one for the DSP, one for the DVD, one for the audio output, one for the GUI... Some hardware features also has their own threads, like wiimotes. But in the end, most of those threads are just idling. The CPU thread matters most, the GPU thread is usually used for 50%.

So the common bottleneck (the CPU emulation) can only use one core. Everything else usually fits within the second core.

I suggest you try and get a 4gb video card if you can. Dolphin does not need it, but the latest PC games will.