Dolphin, the GameCube and Wii emulator - Forums

The i7-4770K should bei ok (I run DKCR on a i5-4670k@4Ghz and it runs smooth, don't know about SMG, don't have this game)
Maybe you should check the BIOS whether Turbo is enabled - becuase your CPU runs @ 3,9Ghz with enabled Turbo
Also update your videocard drivers & DirectX

How are "normal" games - do they run normal?

Try this:

https://forums.dolphin-emu.org/Thread-wii-super-mario-galaxy--25930?pid=302593#pid302593

Salu2 - Darkness Knight