Try these:
1) Update drivers, Windows updates, DirectX Web installer (may be missing some parts), and latest version of Visual C++
2) Make sure under Power Management in Windows you're running in High Performance, and are plugged in to power. Also set a high performance profile under Catalyst Control Center
3) Use the OpenGL backend on one of the latest dev builds, as it is faster than D3D. The current dev build is 4.0-720
I'm pretty sure that D3D9 broke some stuff in SMG (https://dolphin-emu.org/blog/2013/10/12/d3d9-why-its-not-part-dolphins-future/)
Also: overclock that CPU. Extra speed is always welcomed for Dolphin
1) Update drivers, Windows updates, DirectX Web installer (may be missing some parts), and latest version of Visual C++
2) Make sure under Power Management in Windows you're running in High Performance, and are plugged in to power. Also set a high performance profile under Catalyst Control Center
3) Use the OpenGL backend on one of the latest dev builds, as it is faster than D3D. The current dev build is 4.0-720
I'm pretty sure that D3D9 broke some stuff in SMG (https://dolphin-emu.org/blog/2013/10/12/d3d9-why-its-not-part-dolphins-future/)
Also: overclock that CPU. Extra speed is always welcomed for Dolphin