Would I need more than 700-watts for my:
AMD Phenom II X6 1090T Processor, Black Edition
Gigabyte GTX 670 Windforce Overclocked 2gb
Hi - If you already have a 700w unit, it is way more than enough.
A quality 500w (what realhardtechX suggests) is plenty, and
leaves some headroom. If you already have the 700w, please
insure that it is capable of delivering it's specs, check a review
or post brand and model here.
2 - 670's in SLI require only 750w realhardtechX and that has headroom not 1,000w
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 maximum combined +12 Volt continuous current rating of 30 Amps or greater and that has at least two 6-pin PCI Express supplementary power connectors.
For a system using two reference clocked GeForce GTX 670 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 700 Watt or greater power supply that has a maximum combined +12 Volt continuous current rating of 45 Amps or greater and that has at least four 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.
And I'm using a Corsair Hydro Series Extreme Performance Liquid CPU Cooler H100i
The OCZ ModXStream Pro Series 700W (OCZ700MXSP), with its maximum combined +12 Volt continuous current rating of 46 Amps and with one 6-pin and one (6+2)-pin PCI Express supplementary power connectors, is more than sufficient to power your system configuration with a single GeForce GTX 670 graphics card.
The Corsair H100i is not a heavy power consumption device (i.e. less than 20 Watts).