PSU for 680 sli or 670 sli

[Potential]

Hey Tomshardware community. I'm wondering how much power will I need to run my build that I will be buying. I'm currently thinking about an 850W seasonic 80 plus gold fully modular power supply to run my build but I'm not exactly positive if it'll handle everything fine. Also, the power supply I just listed is $160 and after Mail in Rebate it'll be $140. $140 is a great deal especially with a high quality power supply so hopefully 850W will be perfect for either setup. I'll be overclocking a lot too. Heres my build

CPU: i5 3570k (I will be overclocking this to the highest it'll go)
Motherboard: Sabertooth Z77
RAM: 8GB (2x4GB) 1600 MHz
HDD: 1TB 7200 64MB
SSD: Samsung 840 Pro 128GB
Optical Drive, a case, aftermarket cpu cooler, Shitty monitor, keyboard and mouse with audio system.

I'll either be going with 2 Asus GTX 680 TOP (factory overclocked cards) or 2 EVGA GTX 670 FTW cards. So if you could list the minimum power needed to run the build listed above with the 2 680's and list the minimum power needed to run the build with 2 670's. Keep in mind I'll be overclocking heavily! Thanks so much guys!

EDIT: Also for the 680's, since their pretty high factory overclocked I most likely will not be OCing them. As for the 670's I will be overclocking them.

 

[ko888]

For a system using two GeForce GTX 680 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 750 Watt or greater power supply that has a combined +12 Volt continuous current rating of 53 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.

Overclocking of the CPU and/or GPU(s) will require at least an additional 7 Amp 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 is dependent on the magnitude of the overclock you are trying to achieve.

The Seasonic X-Series 850W (SS-850KM), with its combined +12 Volt continuous current rating of 70 Amps and with four (6+2)-pin PCI Express supplementary power connectors, is more than sufficient to power your system configuration with two GeForce GTX 680 in 2-way SLI mode.

 

[Potential]

Best answer selected by Potential.

 

[Potential]

For a system using two GeForce GTX 680 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 750 Watt or greater power supply that has a combined +12 Volt continuous current rating of 53 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.

Overclocking of the CPU and/or GPU(s) will require at least an additional 7 Amp 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 is dependent on the magnitude of the overclock you are trying to achieve.

The Seasonic X-Series 850W (SS-850KM), with its combined +12 Volt continuous current rating of 70 Amps and with four (6+2)-pin PCI Express supplementary power connectors, is more than sufficient to power your system configuration with two GeForce GTX 680 in 2-way SLI mode.

Give this man a medal. Now