That's my understanding. Note that there is also a 4 pin connector with 12V and Gnd which is NOT compatible with the extra 4 pins. Refer to the following diagram. You will have to click on the diagram here to get a readable copy it appears.

 

The new motherboards require a 24 pin power connector. The ATX-2 power supplys have 2 12 volt rails. Some manufacturers of power supplies have now started to build them so that they will work with both the 20 pin mobos as well as 24 pin mobos. If the mobo has a 20 pin connector, per the ATX-1 specs, you can disconnect the 4-pin part to the connector and use it as a 20 pin PS.. It it has a 24-pin, you use it that way. It also has the 4-pin connector for the processor.

 

Correct, my point is that several people have become confused about trying to use the extra 12V/Gnd processor power connector to add to the 20 pin connection. That would NOT work as can be clearly seen from the pinout of the 24 pin connector.

 

Johnwill, I fully agree with you and it would appear from his post that Tacocaster is one of the people that is at least partially confused with the connector issue.

From my understanding, it is made this way as to power a mobo that requires a 20 pin connection and a separate 4 pin connection and it can also be used to power a motherboard that requires a single 24 pin connection. Is this correct?

I was trying to help clear this up with my post.

 

Hmm, Ok so let's get down to brass tax here. I have a 24 pin mobo. Asus A8N-SLI Premium AND I have a 7800GTX which requires its own power. If I understand this correctly, the OCZ Modstream has a 20 pin connector and a 4 pin to use to power for the mobo and it also as an additional 12v, 4pin connector for the PCIe device correct?

 

No. That board uses a 24 pin ATX-2 power supply which has a 24 pin power connector. It also uses a 4-pin 12 volt connector located just above the fanless pipe in the upper left corner of the board. Do not break the 24-pin power connector into two parts. The power supply has another square 4-pin power connector that fits the square connector in the upper left of the board. (Close to the upper left screw hole)

If using more than one video card, plug a 12 volt connector that looks like a HD power connector into the EZ-PLUg located just above the PCI-E slot. If your video card has its own power supply plug located on it, plug the 12 volt (looks just like a HD plug) directly into it.

 

So what you are saying is that the PSU could power a 20 pin mobo that also requires a 4 pin connector for the processor and not power a 24 pin mobo?

EDIT*

Newegg shows these as the following connections:
1 x Main connector (20+4 pin)
1 x 12V (P4)
6 x peripheral
2 x SATA
1 x Floppy
1 x PCI-E

I would use the main connector (20 + 4) and the 12v (P4) to power the motherboard correct? Then I would use the PCIe for the video card?

 

no. What I am saying is that the 1 x Main connector (20+4 pin) can be broken apart to feed either a 20 pin power connector on a motherboard or not broken apart and it will feed a 24 pin power connector on your new Asus A8N-SLI Premium. If someone had a 20 pin motherboard connector and needed to break apart the 24 pin connector it would then power that board. But if you did break apart the 24 pin, don't use the resultant 4 pin connector to power anything else. The voltages are not correct.

Your use under your EDIT is correct..

 

There are the two MB connections.

1 x Main connector (20+4 pin) *** leave these together ***
1 x 12V (P4) Two yellow & 2 black wires.

 

Gotcha, thanks for all the help.