Where is an easy place to figure out how much power I need to get to my system? My old PS just died (400 watt Antec) and it was sort of fluxing under the load I had on it. Currently I am running an A64 + 6800GT + 4 HD (2 raptor 2 normal) + 2 dvd drives + Koolance EXOS - would the Antec TrueBLUE 480 be enough?