Congrats on buying the parts and keep posting here I wouldn't mind seeing that machine being set up. Besides if you have another other questions when the rig is set up I am sure people on here are more than happy to help. So far if there is a ceiling on dolphin being able to use the gpu I haven't hit it because when you start to go above an IR of 4k with SSAA my gpu takes a hit and the game comes crashing down to a crawl.
Intel i5-4690k @ 4.6 GHz | Gigabyte GTX 970 4GB G1 | 8 GB DDR3 @ 1600 MHz | Windows 10 TP | Dolphin 4.0-6811