Get an Nvidia Gpu. They allowed desktop recording in their new driver update. It doesn't hit the cpu hard and barely hits the gpu(5-10%) so that is your best option for recording dolphin with your current cpu. I'd recommend either a GTX 660 or 750ti. Both perform similar(except the 750ti uses a lot less power which is great.) And they both support shadow play which is what the software will need.
Gaming Rig
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