Reason I ask is because I've modeled just about the same build on Newegg.com's wattage calculator and I get something around 550 watts instead of what is given with PcPartpicker.
Note: this is my personal build right now minus the GPU. The GPU selected is something I wish to upgrade to for the new release of Fallout 4 as I currently have an Asus GTX 660... as well as GTA V