2 way SLI Nvidia Geforce 660 ti

Haza

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Apr 20, 2013
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Hi, I have one of these graphics cards and I am hoping to add a second card with SLI, but my question is how powerful must my PSU be to run 2 of them.

My power supply is a Corsair CX600w.
 

carowden

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well regardless, your power supply only has 2 pcie connections. I would not run the second 660ti off of molex to pcie adapters. I would suggest 700-750 watts for a new psu and make sure that it has 4 pcie connectors
 

fatboytyler

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I would advise against it, as the 660Ti can draw near 300W under full load depending on the brand. So two of them plus the rest of your system, you'd be really pushing it.

Side Note: That wattage was based off of one bench that I looked at, so others may say otherwise.
 

Haza

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Thanks for the answers, my here some other specs:
CPU: Intel core i5 3570k @ 4.5ghz (cooled by Corsair H55)
RAM: 2x 4gb Corsair Vengeance 1600mhz
Motherboard: Asus P8Z77-V LX
 
For a system using two GeForce GTX 660 Ti graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 650 Watt or greater system power supply that has a maximum combined +12 Volt continuous current rating of 38 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 an additional increase to the maximum 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 being attempted.

The Corsair Builder Series CX600 (SKU# 75-001668 / CP-9020048), with its maximum combined +12 Volt continuous current rating of 46 Amps and with two (6+2)-pin PCI Express supplementary power connectors, is electrically sufficient to power your system configuration with two GeForce GTX 660 Ti graphics cards in 2-way SLI mode. You will need to use a couple of PCI Express adapter cables.

These PCI-E Y Splitters are better, you'll need two of these, since they use only the existing two PCI-E cables from your CX600:
http://www.newegg.com/Product/Product.aspx?Item=N82E16812201038&Tpk=PCI%20Express%20Y%20splitter&IsVirtualParent=1
 

fatboytyler

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While this is good information and correct, if you tryto draw more than the maximum power rating then the whole system will boggle or worse, the PSU goes and brings some components with it
 


He is right... BUT its too damn close for me...
 

HardwareGTX

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Two regular non Ti 660's would work since they only need 1x6pin each, And the regular 660 should be fine especially two in SLI. But I don't see any reason why using the molex would hurt, I have never heard of any problems with people who had to use a molex adapter, My brother has used one for 3 years for a 5870, It is a power plug just like the 6-8 pin power plug, I see absolutely no reason why it would automatically be dangerous just because it needs a adapter to be used. If it was dangerous they would not include the adapter and they would void the warranty if you used one. I think it is just a narcissistic rumor from people with high dollar rigs.
 


A single 660Ti will draw about 150w not 300w and as I'm running two of them on a 620w PSU that only has two PCIe connectors and is using two molex connectors and haven't had any problems I think the OP might get away with it providing they are using a good PSU and not a cheapo one.