ASUS Mars II video card and Corsair AX 1200 install

[unclepauly28]

I need some help with hooking up an ASUS Mars II video card to a Corsair AX1200 PSU. The Mars II has 3 8-pin connectors and it came with two 8-pin plugs. Each of these 8-pin plugs have two 6-pin connectors coming off of them. One of the 6-pin connectors have all 6 active and the other has 5 active with the one in the middle of one row blank. I am assuming I will use the 5 PCI-e plugs that came with the PSU to connect this beast this way. One PCI-e plug will use all 8 pins in one of the Mars II 8-pin connectors and will connect straight to the PSU. The other 2 Mars II 8-pin connectors will be connected to the two 8-pin plugs that came with the Mars II. Then each of the four 6-pin connectors will be connected to the 6-pin block of the other 4 PCI-e connectors which will connect to the PSU.

I hope this is clear. If not and you're still willing to help email me directly and I will send a Word document with a block diagram.

Thanks

[zburns]

UnclePauly,

I think you are making things too complicated. You have three 8 pin male plugs on the top of your graphics card. This means one thing only, each 8 pin male plug must receive a 8 pin female plug from the psu. The amount of wattage delivered by one 8 pin female plug to one of the three male plugs on the card is 150 watts maximum.

Three plugs mean you have the capability to deliver a total of 3 X 150 watts or 450 watts total to the graphics card. The pciex16 slot does have a psu connection thru the slot and the amount of maximum wattage that can move thru the 16 pin slot is only 75 watts. The total wattage the card can receive is 75 watts plus 450 watts for a total of 525 watts.

Note: Over several years I have only seen the following: Power is fed to a gpu card via the 16 pin slot for a max of 75 watts. A single 6 pin connector will accept 75 watts. A single 8 pin connector will accept 150 watts.

Repeating myself: You have three 8 pin male connectors on the card. They must be fed by three 8 pin female plugs on one single cable from the psu. Lastly, the 16 pin slot will provide 75 watts.

All of the above is from the current ATX standard that all your components must meet.

Also when you make reference to a plug, you count the number of openings whether they are used or not. The pins that go in each of the openings, or, just some of the openings are either male or female -- a plug can only be all male or all female (you cannot mix male and female pins in the same housing).
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Your card has three 8 pin plugs. Each plug has 8 openings for pins. The pins in an individual plug are either all male or either all female (depends on which direction the power comes from; female plug brings power from the psu; male plug on the card receives the female plug)

In your case, you must have three separate cables from the psu, each cable going into a female housing with up to 8 female pins (some may be missing because they may not be needed). The female with pins plugs into the male housing with matching male pins.

The three female cables all must come from the psu (this becomes a separate issue, because each female cable must be go to a rail capable of delivering 150 watts. If the rail is capable of delivering 450 watts or more then all three cables can come from the same rail.

[zburns]

For your information, Rob does not permit e-mailing between two forum members in a situation like this. We have to use the forum and write it all out!
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I have pulled up your Corsair PSU manual at this URL: http://www.corsair.com/en/media/cms/manual/49-000037_revAB_AXManual_Webversion.pdf

On page 8 of the manual, for the 1200 watt version, it states that you have 6 PCI-E cables and each cable has one connector per cable. (from page 9)They provide only one instruction and I quote directly from the manual: "c. Connect the PCI-Express cables to the power sockets of your PCI-Express video cards if required" -- this from page 9.

They do not state how many pins there are on the 'one connector per cable' (6 or 8, they do not specify either one).

My comment: Does the data I just mentioned from the online manual match exactly what you have or not. If different, what are the differences.

Without knowing or seeing a circuit diagram, I would assume that each PCI-E cable can only go to one of the 8 pin video card 8 pin male plugs, but I would not plug it up without knowing for certain that it is correct.
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Question: On your 6 PCI-E cables coming from the psu, is the female plug at the end of the cable a 8 pin or 6 pin?

[unclepauly28]

Thanks for your help. When I posted originally I was making an assumption that ASUS intended for those cables that were included with the card to be used in some manner of powering the card. After going back and staring at the card and the PCI-c connectors from my AX1200 it became obvious that using these directly to the card was the most sensible solution as you pointed out.

Again, thanks for your help. It helps to have confirmation from a pro.

[zburns]

Do not let this post confuse you! Also, please do not take any action regards your build because of this post. It is a post for 'information only' and may or may not be totally accurate info.

Those 8 pin male plugs on the video card are for the sole purpose of bringing in 150 watts of power from the psu to each plug. 8 pins is the 'ATX' requirement or standard to 'get' the 150 watts.

Now, here is the confusing part. It only takes two wires to bring in the 150 watts or 75 watts. That leaves a big question mark on the 'other 6 pins' and no where in the 'computer literature' that I have read over several years have I seen 'exactly what the other 6 pins are used for. However, an educated guess is the following: First, the 8 pins are for 150 watts. A six pin plug is for 75 watts. How do you force the video card to accept 'only 150 watts of power', or, alternatively, 75 watts of power on a 6 pin plug. Such differentiation between a six pin plug and the eight pin plug is accomplished by using two pins for a simple 'loop' circuit to force the computer to feed in 150 watts in lieu of 75 watts -- I do not know that it is done this way, but it is the 'simplest' way to do it, circuit wise.

On the eight pin plug, an extra two wires or perhaps only one wire are (is) used to allow the psu to deliver the extra 75 watts, and, also allow the video card to accept the extra 75 watts. (without seeing the actual circuit, I cannot be specific, but it has to be as 'simple' as I describe it)

My point in even bringing this up is the fact that some adapter cable may have a plug on it that is missing a pin, ie. 7 pins in lieu of 8 pins.

This post is an effort just to shed light on the difference between 6 pins and 8 pins on video card power plugs. Nothing in this post is 'any suggestion that you should use regards your present build' -- information only.

[zburns]

After going back and staring at the card and the PCI-c connectors from my AX1200 it became obvious that using these directly to the card was the most sensible solution as you pointed out.


I assume that the plugs on the cables from the psu that you refer to, are 8 pin plugs. Assuming that is the case, logic would dictate that a number of the PCI-E plugs would be 8 pin because it is a 1200 watt psu, and, therefore, to utilize the 1200 watts, the plug configurations must allow the psu to put that wattage out there via the 8 pin plugs.

I looked in the on line manual, and, it did not tell me whether the plugs were 6 pin or 8 pin.

Again, I am just trying to convey information, not suggesting you 'act' on it!!

Good luck!

[unclepauly28]

The configuration of the PCI-e connectors that came with the AX1200 are as follows.

PSU end pppp solid 8 pin plug
pppp

COM end p ppp a solid 6 pin plug and an "optional" 2 pin plug
p ppp

I FINALLY got someone on the phone from ASUS tech support who seemed to be truly knowledgeable about this card. He said not to use any adapters when connecting this card; to use the PCI-e connectors straight from the PSU to the card.

[zburns]

to use the PCI-e connectors straight from the PSU to the card.

Do you have three PCI-e 8 pin connectors coming direct from the psu?

[zburns]

I found this Corsair site regarding the cables: http://www.corsair.com/en/power-supply-units/psu-accessories/professional-series-gold-ax1200-individually-sleeved-modular-cables-blue.html

In the dialogue on the page you will pull up, the following specification: Six (6) PCI-Express Connector 8 pin (6+2 split) Individually Sleeved Modular Cable, Blue
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1. This sentence just above implies to me or directly tells me that to get 8 pins, it is a split cable connector made up of a 6 pin connector plus a 2 pin connector.

2. Assuming you multiple PCI-E cables from the psu and that EACH cable is made up of a 6 pin female connector plus a two pin female connector, then both should fit into one of the 8 pin video card male connectors.
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Note: There design is such that it is nearly impossible to make a mistake when plugging them in. The design should be such that there is only one way the female plug will go on the male plug.
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A single PCI-E cable end should have a six pin plastic male plug with a two pin plastic male plug adjacent to the six pin -- both plugs part of the single cable coming from the psu.

[unclepauly28]

That is true. There were 5 of these 8 pin PCI-e connectors that came with the PSU. To clarify my previous post:

PSU end - solid 8 pin plug
pppp
pppp

COM end - a solid 6 pin plug and an "optional" 2 pin plug
p ppp
p ppp

And you are correct. The locking pin allows the connector to go in only one way.

[zburns]

Great!! Glad you got a handle on it. Just a general comment. These are 'molex' type plugs. The company Molex was the first company ( I think ) to come out with the initial design, many years ago, of these type plugs. In general, these type plugs are used in huge numbers by electronic product manufacuters.

The great thing about them is that it is virtually impossible to make a mistake with them, as you have found out!!
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I assume the following: Corsair did not leave you with any choice in the way you used them. You are forced to use them only one way.