PSU Confusion

Hi Everyone ,

I don’t know which PSU would be the best for my System. I used several PSU-calculators, each with ranges from  450W up to  650 Watt . with some “Peak Settings”  even more…

I want to build a system with this Hardware

CPU: AMD FX 8350

CPU Cooler: Thermalright Hr-02 Macho Rev. A (BW)

GPU: Sapphire Radeon HD 7870 OC

Motherboard: Gigabyte GA-990FXA-UD3

Ram: G.Skill Ares F3-1866C9D-8GAB

A Case with 3 Led 120mm fan

A 2TB Seagate HDD

First I don’t want to overclock the System, but  maybe  later

All i know  is  that the AMD CPU is really  Hungry....

So please help me, which PSU would be the  best for this  system  with  and  without  overclocking?

Thx for your  help :)