Help on PSU on new build

Hi just about to upgrade my pc, but stuck on the amount of watts on PSU and which model. Here are the parts I will be using.

Processor - Intel i7 4770k (overclocking)

Motherboard - Asus Z87 Pro

Memory - not sure yet but using 16-32 GB

GPU - Gigabyte GTX 460, but will be up grading soon not sure to which GPU or single or dual cards

Case - Antec 1200 with 7 120mm fans and 1 140mm fans

4 hard drives 3TB each

2 SSD hard drives

any help would be appreciated

550W / 650W is more then enough ☺ look at the corsair RM or HX series.