# ATX 12v 8 pin and 4 pin connectors question



## jgoff14

Got a Asus Maximus VI 

http://i.imgur.com/PIfAUFt.jpg

My question is that the item labeled "3" at the top left is a 12v ATX 4 pin and an 8 pin. In the manual it says connect either 4 pin or 8 pin so which do I want, and it say the 4 pin can be plugged in to the 8 pin socket so why both? Are they for different things?
i7 4770k
16gb Corsair Vengeance
EVGA 1000W 80+ Plat
Samsung 840 pro 256gb SSD
EVGA GTX 780
There will be no overclocking on this system at all. Please explain what they are for and why there are 2 sockets if the manual is telling me that regardless of choice I really only need the 8 pin. Thanks in advance!


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## Okedokey

If your PSU has an 8 pin CPU connector, use that.  It will provide more power to the CPU especially when overclocking.   A 4 pin will work, and in some cases that is all that some people have.

Use the 8 pin, it will provide more power.

Also connect a molex plug to the EZ_Plug (number 3 at the bottom), this provides more stable power to the PCIe lanes.


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## Jiniix

The board is meant for overclockers. Everyone who buys that board is expected to have an 8-pin CPU connector in their PSU. But they provide an _additional_ 4-pin if you are going to do extreme overclocking, to ease the strain on the 8-pin.


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## Okedokey

Jiniix said:


> The board is meant for overclockers. Everyone who buys that board is expected to have an 8-pin CPU connector in their PSU. But they provide an _additional_ 4-pin if you are going to do extreme overclocking, to ease the strain on the 8-pin.



Incorrect, you use one or the other, not both.


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## kdfresh09

^..im using both 8 pin and 4 pin on my asus maximus v formula.  seems to work great as I can get my 3770k to 4.7Ghz with 1.35v.  id say go ahead and use both the 8pin and 4pin.  it will only provide better power stability, and WILL NOT cause any problems


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## Okedokey

It wont increase stability to have both, and clearly says in the manual OR.







And given that the 8 pin EATX 12V connector can deliver 288W, connecting the tertiary 4 pin (144W) connector is completely unecessary unless of course you think that your CPU will somehow draw 36A lol.


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## kdfresh09

well said okey.  didn't look at it this way.  all I read was in the manual that came with this ROG board, was to "plug both cpu power connectors if I had the ability to for better overclockability"...although, im assuming they are meaning if I chose to use liquid nitrogen for my cooling?  either way, they are plugged in and all is well, so, to the O.P., its really up to you.  either way you go it will be fine

and okey, not to be anything other than observant, the cpu wouldn't pull 36a, if it needed both 288+144w....it would be 3.6a. simple decimal error, it happens.


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## Okedokey

kdfresh09 said:


> and okey, not to be anything other than observant, the cpu wouldn't pull 36a, if it needed both 288+144w....it would be 3.6a. simple decimal error, it happens.



What is 288 + 144 W?

Answer: 432W

How many amps is 432W at 12V DC?

Answer:  432 / 12

= 36A.

Simply sense check would have resulted in the fact that 3.6A is not enough to even run the likely scenario of a 120W processor at 12V as that by itself is 10A.

A simply misunderstanding of ohms law i suspect?


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## Cromewell

Except a CPU doesn't run on 12V. It's VRM does.


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## Okedokey

Cromewell said:


> Except a CPU doesn't run on 12V. It's VRM does.



Yes, but for the purposes of this discussion, its a 12V loading.


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## kdfresh09

to okey...no, my mistake for sure.  I used 120v ac instead of 12v dc in my math.  was thinking at the outlet, and not the psu.  duh on my end;  I should know better.


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## Okedokey

kdfresh09 said:


> to okey...no, my mistake for sure.  I used 120v ac instead of 12v dc in my math.  was thinking at the outlet, and not the psu.  duh on my end;  I should know better.



All good man.  Always a good idea to sense check by reversing the calculation.


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## kdfresh09

for sure.


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