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Okay, he's building a new computer, gonna get into SLI. He needs a power supply that is powerful enough to power about 8 LED 120mm fans, water cooling, 4 Hard Drives, 2 XFX GeForce8800's, a high-end motherboard, 4 gigs of OCZ Platinum Series DDR2 800 RAM, a Core 2 Duo processor, and 3 optical drives (CD/DVD burners).

Thanks!
 

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If you do the Power Supply calculator, it shows up as needing 1000w and that's before adding the 30% buffer. You are looking at needing a 1300w PSU. My recommendation is to drop lose a few things and drop it down to needing a 850w PSU and you'll do good with this one:

http://www.newegg.com/Product/Product.asp?Item=N82E16817341003
 

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That is if anyone else on here has another idea.
 

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Matt has the right PSU for that rig!


wow thats some big bucks


I am patiently :laugh: waiting for a customer like that so I can build an all out machine!
 

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that model PC Power & Cooling is one of the few that have been successfully tested to work with a pair of 8800's!



yes; the pair of 8800's toghether need 34 amps give or take /
divided by two for multi rail and you will need a minimum of 19 amps per rail to run that "predator"

seeing as how the max spec for the ATX multi rail design is 20 amps per 12 volt rail its cutting it really close; too close actually for a multi railed unit! I would not try to run that rig with a multi 12V rail unit.


The PC Power and Cooling unit above has 72 amps on a single rail to get around the max 20 amp spec for multi railed PSU's therefore you will have almost one half the capabilities for the powering of the rest of the system! thats very dooable! but only with this unit that I am aware of ????
 

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Another reason I chose that PSU is that the 8800GTX cards actually have two 6-pin PCIe power connectors on each card, so to run them in SLI would require 4 x 6-pin PCIe connectors.
 

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ahhhhhh nice catch Matt! 2 PCI express connectors for each card I was puzzled why that PCPC unit had so many PCI express plugs; but I was too darned tired at the time for the light to come on! :sleep:
I was thinking, wait, even sli only needs two :4-thatsba duhhhhhhhh
 

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that model PC Power & Cooling is one of the few that have been successfully tested to work with a pair of 8800's!



yes; the pair of 8800's toghether need 34 amps give or take /
divided by two for multi rail and you will need a minimum of 19 amps per rail to run that "predator"

seeing as how the max spec for the ATX multi rail design is 20 amps per 12 volt rail its cutting it really close; too close actually for a multi railed unit! I would not try to run that rig with a multi 12V rail unit.


The PC Power and Cooling unit above has 72 amps on a single rail to get around the max 20 amp spec for multi railed PSU's therefore you will have almost one half the capabilities for the powering of the rest of the system! thats very dooable! but only with this unit that I am aware of ????
8800s dont need 19a each, they dont consume 228w and they dont draw it from just the pci-e psu connectors, the pci-e slot gives 75w, and its not just 12v... here you can see the whole system only consumes a little less than 500w http://www.hwupgrade.com/articles/video/13/the-nvidia-geforce-8800-gtx-and-gts-in-sli_5.html however a good 850w/1000w psu wont hurt as it wont be running near max capacity at load.
 

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The PCI-e slot is able to deliver 75W without any external connector. The GeForce 8800GTX (GTS comes with one) comes with two connectors, so it could draw up to 225W.

nVidia recommends 450W or higher PSU (with 12V rating of 30A) for 8800GTX and if you want to run these cards in SLI you have to double that figure. The GTS requires 400W PSU (with 12V current rating of 26A).

Put everything else he has on load and he does need a 850W+ PSU and 1000W is accurate enough to be safe with good amperage and efficiency.
 

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this site shows just the video cards at 378watts for two 8800'sgtx

http://www.atomicmpc.com.au/forums.asp?s=2&c=7&t=9354


I am very skeptical you can run that system with a balance of 86 watts ???? to get to their 464 watts @ full load

the CPU alone will consume 100 watts, now add memory sticks, motherboard, usb devices (each one) sound card cooling fans ???????


notice what PSU they used to test it with, I saw another similar write up where they used a Enermax Galaxy 1000 watt.

The only thing I know for sure; thats alotta cash !


Thanks for the link & discussion, good reading.
 

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im not sure what you said, but in the review, the whole system is consuming 464w, not just the cards edit: oh, the link you gave, ill see, odd that two sites get such different readings.. wait, they didnt actually measure the cards, they took it from the psu calculator site. while, their max theoretical output maybe 380 watts, in real life, its very unlikely that the game will be able to drive the cards to full load.
 

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dont forget the watercooler & 4 sticks of ram & 3 optical drives


the watercooler alone tanks alot of systems that didnt have alot fo headroom
 

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And if those four hard drives are WD Raptors or high end SCSI drives, then they will eat up power for the motors as well.
 
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