Above, a chart of relative power consumption. Again the Wattage shown is the card with the GPU(s) stressed 100%, showing only the peak GPU power draw, not the power consumption of the entire PC and not the average gaming power consumption.
Here is Guru3D's power supply recommendation:
GeForce GTX 670 - On your average system the card requires you to have a 500~550 Watt power supply unit.
GeForce GTX 670 2x SLI - On your average system the cards require you to have a 700 Watt power supply unit as minimum.
GeForce GTX 670 3x SLI - On your average system the cards require you to have a 850 Watt power supply unit as minimum.
Remember, if you are going to overclock the GPUs or processor, then we do recommend you purchase something with some more stamina. The minute you touch voltages on the CPU or GPUs, the power draw can rise real fast and extensively.
Taken directly from your 2nd link. I made my recommendation........I'm done
Before I read the 2 dozen replies above (I'm short on time at the moment), I want to explain these recommendations again: these are for
peak-rated PSUs. I'll break it down:
A 500-550W peak-rated PSU would have a +12V capacity of about 360-396W, or 30-33A. That's what some good quality-made 400W PSUs have (i.e. continuous-rated PSUs).
A 700W peak-rated PSU would have a +12V capacity of about 504W, or 42A. That's the +12V capacity of many good quality-made 520-550W PSUs and even some 520-530W PSUs.
An 850W peak-rated PSU would have a +12V capacity of about 600W, or 50A. That's the +12V capacity of many good quality-made 620-650W PSUs. Actually, 624W or 52A is a more common +12V capacity for good quality-made 650W PSUs, but still.
So I stand by what I said and I will never back down. You can think that I'm wrong all you want and you can continue contradicting me all you want, but I know I'm right. If you want to prove it, then ask the PSU experts over at JonnyGURU.com. They don't know me yet (because I don't yet feel confident to be one of their equals), but I guarantee you that they will tell you that I'm right. So go ahead and ask them. If you don't want to ask them, then I would appreciate it if you would stop trying to tell me I'm wrong because I don't waste my time when I'm only 99% sure. I wait until I'm absolutely 100% sure.
Thank you in advance.