For a system using a single GeForce GTX 670 graphics card NVIDIA specifies a minimum of a 500 Watt or greater power supply that has a combined +12 Volt continuous current rating of 30 Amps or greater and that has at least two 6-pin PCI Express supplementary power connectors.
Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Total Combined Continuous Power/Current Available on the +12V Rail(s) rated at 45°C - 50°C ambient temperature, is the most important factor.
Overclocking of the CPU and/or GPU(s) will require an additional increase to the combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the overclock. The additional amount required will depend on the magnitude of the overclock you are trying to achieve.
The Corsair Builder Series CX600 V2 (CMPSU-600CXV2), with its combined +12 Volt continuous current rating of 40 Amps and with two (6+2)-pin PCI Express supplementary power connectors, is more than sufficient to power your system configuration with a single GeForce GTX 670.