For anyone that tries this route, following random tutorials on VGA PCI Passthrough is a route to sure frustration and time wasting (I tried it ~2 or 3 years ago, whenever I built my previous PC). You have to make sure your video card, motherboard chipset, audio, and anything else you want to pass through are all supported. It's much simpler if you can just follow a list that says "this combination of hardware + software works perfectly."