On the wattage of overclocking (new PC build)

So I was talking with my friend the other night about the new build I want to buy. The friend in question generally knows is stuff when it comes to computer so I was suprised when he told me that overclocking required a bigger PSU. I said OK, this makes sense, but he told me I would need a minimum of 750W of power.

Problem is, the power supply I bought is only 550W as all the tools I used and indications on the graphics card's box said 450W would be OK. By the way, here's the rest of my build: http://ca.pcpartpicker.com/p/Lbvn (suggestions are always appreciated, my buget is 1000$)

So my question is, if I plan to overclock, will my current power supply will suffice or I need to return it and find one with more power?

470W is recommended by the Newegg psu calculator, will 550W with overclocking be enough? I don't exactly know, because I have no idea how much more watts the CPU needs when being overclocked. Im just gonna wait for some other replies.

650/750 W is allways safe

http://goo.gl/Es7l

Not 750w minimum, i would say if you don't plan on getting another graphics card you might already be good,  if you realy want to be safe just get a 650w and be done with it. 

+1, 650W is the sweet spot for gaming systems, overclocks any processor and a modern single graphics card in a case with normal peripherals. It used to be higher, but then graphics cards became more power efficient.