Help with my PC (Radeon HD 8330)

[Sonatok]

Hello everyone and thanks in advance for your help. I recently started using this emulator for Wii and GC but all the games I've tried to be very jerky, why?How can I best configure dolphin?

My PC specifications are:

CPU:AMD A4-5000 (quad-core, 1.5 GHz)
GPU:Radeon HD 8330
RAM: 16 GB
Window: 8.1 x64

Thanks