How many watts for GTX 780 SLI?

Twisto Gopro

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Oct 6, 2013
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How big should my power supply be for 780 sli?

Some people say 750w and others say 1000w

I got an i7-4770k too..

Atm i got a Corsair CX750w
 

IAMEXTREME

Honorable


I will totally disagree with you.

A decent 750watt is enough for GTX 780 SLI!.

A single GTX 780 use 250 watts under load (not over clocked).
2 way sli GTX = ~500watt

The rest of the system will require about 150~200 watt.
 

Marley217

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Nov 29, 2013
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I don't think you understand how a psu works. There is no 100% efficient psu, most are about 80% efficient. Which means that your 750 watt psu will only provide +- 600 watt. I have a 600 watt psu, and run a single GTX 780. If I overclock the gpu only a little I run out of power and the systems shuts down. Please stop giving false information.
 
For a system using a single GeForce GTX 780 graphics card NVIDIA specifies a minimum of a 600 Watt or greater system power supply that has a maximum combined +12 Volt continuous current rating of 42 Amps or greater and that has at least one 6-pin and one 8-pin PCI Express supplementary power connectors.

For a system using two GeForce GTX 780 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 850 Watt or greater system power supply that has a maximum combined +12 Volt continuous current rating of 65 Amps or greater and that has at least two 6-pin and two 8-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) rated at 45°C - 50°C ambient temperature, is the most critical factor.

Overclocking of the CPU and/or GPU(s) may 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.
 

Europa2097

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Jan 8, 2014
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And I am not sure you understand the way a PSU works either. The wattage indicated on the PSU is the output Wattage, not the input Wattage. So the power advertised is the one your components will actually get. For instance, if a 800W PSU is rated 80% efficiency, that means it will provide 800W to all your components but will draw 1000W from the electric socket (http://en.wikipedia.org/wiki/80_Plus#Technical_overview).
I've seen this error so many times because people always think the power advertised on products is the one that will impact their electrical bill :).
 


Hi - See ko888 post above. The key factor is the +12v amps available. 65 +12v amps is recommended, more for OC.
The CX750 has 62 +12v amps. It is reasonable to assume if you have a "K" processor, you intend to OC.

Considering you are short on +12v amps to begin with, you should upgrade to a good quality 850w or greater PSU.
I might also suggest considering your current components being of a high end nature that you step up in
quality from a budget/entry level PSU such as the CX series.

If you post a budget, we can assist you in finding one.

 

Marley217

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Nov 29, 2013
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Damn, I guess I was wrong. My old 600 watt psu had a max wattage output of 450 watt. I guess I misinterpreted that as low efficiency... Sorry guys
 

Jack Handy

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Mar 12, 2014
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If I were you I would get the power supply I have seeing as we have similar builds. I have a Corsair AX860i and it works amazingly well with my GTX 780s in SLI and 4770K OC'd to 4.4 GHz. You could save a few bucks getting the AX860 instead. I just wanted the added features of the i edition. Stellar power supply.
 

Navoan

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Jan 24, 2014
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I got a pretty similar setup

I7 4770k @4.2
asus gtx 780 sli
seasonic 850 gold

And i try'ed to check the watt with a power consumption meter and it goes from 550-650W during games in BF4

So i say a 850w gold is more than enough :)
 

Inky_Enston

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Jun 3, 2014
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I have four rigs, one is a 4770k @4Ghz with two gigabyte Windforce 780Ti's OC in sli using a Corsair CX750 and has been for a year with absolutely no issues with both gpu's hitting the 100% mark in benchmarks. I also have a 4770k @4Ghz with two Gigabyte Windforce G1 Gaming SOC 970's in SLI using a CX750M with no issues ( including 4x HDD, 1 SSD, H100i and 6x fans) and have just briefly tried two Gigabyte Windforce 780's in SLI with a Corsair SV650 and a 4770 which ran Valley at full chat for 30 minutes with no issues but have now installed a Corsair RM750, just in case.

In a nutshell, the "recommended" is advisory because they (the manufacturer) are covering their backs and simply don't know the quality of the users PSU nor the extra hardware they may have connected. I'm sure better and higher wattage psu's are a better call but for the short term (at least 6-18 months) with minimal other extra crap installed, a 700 - 750w will have no problem with any (all) dual gpu solutions.

Like the term "bottleneck", "850w" is used fast and loose.