What power supply req to Sli 2 x 260 GTX
what is the recommended power supply to run 2 x Gainward Geforce 260 GTX Golden Sample cards?
For a system running with two GeForce GTX 260 graphics cards in 2-way SLI mode a power supply with a minimum 650 Watts or greater with a maximum combined +12 Volt continuous current rating of 51 Amps or greater and with at least four 6-pin PCI-E Supplementary Power Connectors is recommended.
The combined +12 Volt continuous current rating of 51 Amps or greater specification is the most important to meet not the power supply's total wattage.
You don't need that much power.
Pair of GTX260's: 22 - 25 amps.
OC'd CPU: 10 amps.
Rest of system: 100 watts.
That's about 500 watts. Add 10% for Mr. Murphy (of Murphy's Law fame ).
So bare minimum - a very good 550 watt PSU.
Practical minimum is a 650 watt PSU. Unfortunately, most 650 watt power supplies only have 2 PCIe cables.You could always use adapters, but I do not like adapters.
Seasonic makes the only 650 with 4 PCIe cables:
And it is a little expensive.
I'd use something like a Corsair TX750V2:
My mistake. I was basing my calculations based on the older 65nm fab process GPU that consumes more power than the 55nm - 216 SP GPU that the Gainward GTX260 896MB GS uses.
In the worse case power scenario (e.g. running FurMark or OCCT GPU stress test) using a single 65nm version GTX 260 graphics card may draw up to 15.5 Amps from the +12V rails. The 55nm version may draw up to 14.0 Amps.
Under a gaming graphics load a single 65nm version GTX 260 graphics card may draw up to 12.92 Amps from the +12V rails. The 55nm version may draw up to 10.92 Amps.
Overclocking the GPU will, of course, increase the power consumption.