Ok well I have a 3570k with a H50 watercooling unit and i plan to oc it heavily. If i bought the 670, i plan on ocing it as much as i can. that being said, would a corsair cx500 v2 be good enough? i found it for $30 so thats why otherwise i would get a higher wattage
Yes, it has enough amps for the 670 gtx and your system wont reach more than 400w(or about that), but with oc(cpu and gpu, and the rest you'll have) it can reach to ~450w(max load) and that's cut it close to a low entry level of psu from corsair.
The xfx 550w has more room and quality(it was made by seasonic).