Just a few suggestions before your thread gets spammed with builds. Go with an Intel CPU; WoW heavily favors Intel, and they perform much better.
Going with a microatx build is usually more expensive than a regular ATX build. At least last time I checked it was; specifically the motherboard being the same cost or more than that of a regular ATX board.
I don't think there's a such thing as maxing out WoW, either.
I play on 1440p, get anywhere from 150-200 FPS on Ultra in Stormwind, but during raids when there's a lot going on, it can dip anywhere to 30-60 FPS.