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15 February 2010
Author: Giorgos Lazaridis
PC Power Connectors

SATA 15 pins power supply

The newcomer is still too weak to replace the old -macho-4 pins peripheral connector. Obviously, it was not designed for this reason.

There are adapters that convert the old 4-pins peripheral power connectors to the new SATA 15-pins connectors. These adapters are unable to provide the +3.3V that the SATA power connectors have introduced, and therefore must be used with extreme caution.

This is the newcomer (since 2003) that will replace the old peripheral power supply connectors. No, it will not. It is very sophisticated connector, but due to its low current rating, all power supplies still have (and will have) the good old 4-pin molex muscle connectors, to power current draining devices. It carries the same features as it's ancestor, and also has a +3.3 volts line. Although it has 5 cables, it has internally 15 pins. It is physically polarized to avoid errors in connection.

Now here is a point that needs of your attention. This is something that most of the people i know are not aware of. When the power supply has no more SATA power connectors free, or no SATA power connectors at all and you need to power a SATA device, there are cable converters to convert from the old 4-pins to the new 15 pins (5 cables) connector. Do you notice something strange in the previous sentence? Yes, a cable is missing. These connectors are unable to supply the newcomer's innovation, the 5th wire with the +3.3 volts. Most of the times, the devices that are powered with such connectors, does not require external 3.3volts power supply, and believe me, this is not accidental. And as time passes, this is subject to change. So be very careful when using such adapters.

Part Numbers:
CableTerminalsMax current
(per pin)
Molex 67582-0000 Molex 67581-0000 1.5 A


PCI Express power supply
PCI Express 6 pins power supply

For the power-demanding PCI express cards such as the graphic cards, the PEG cable provides three more +12v lines

Be extra careful if your power supply does not have a PEG cable and you use a market cable converter. It comes with two 4-pins peripheral connectors that MUST be connected into separated lines from the power supply!

This connector is used to power demanding cards in PCI Express slots. Such cards are usually the graphic cards. Some of them have more computing power than my laptop! The PCI express slots can provide up to 75 Watts. If more power is required, then this connector provides the power. And because usually the demanding cards are the graphic cards, this cable is called "PEG" (PCI Express Graphics). It can also be connected in an 8-pins PCI Express connector. It is designed to do it. Some cards may operate this way, some may not accept it, as they have enhanced sensor to check if a 6 or an 8 connector is connected. Some cards may accept the 6 pins connectors, but will reduce the performance accordingly. The connector is physically polarized to avoid errors in connection.

Part Numbers:
CableCardTerminalsMax current
(per pin)
Molex 45559-0002 Molex 45558-0002 Molex 39-00-0168
Molex 44476-1111
8 A

2YELLOW (or unconnected)+12V

If your power supply does not have a PEG cable, then you can use a cable converter from the market. These converters have 2 separated 4-pin molex connectors that MUST be connected into different power supply lines.

PCI Express 8 pins power supply

The PCI express cards seems that have grown big. Actually so big, that the 6 pins 12V power connector was not enough any more. So, since 2007, the 8 pins +12V power cable was introduced. This cable can provide double the power than it's ancestor, that is up to 150 watts of raw power. This connector is also polarized to avoid error in connection.


PLEASE CONTRIBUTE! As i do not yet have any photos of an 8 pin PCI-E and a 6+2 PCI-E cable, i search for original (AND ONLY ORIGINAL) photos with analysis larger than 1600x1200. Please email me! Webmaster. Do not confuse this connector with the 8-pins 12V power supply connector, as their polarization is different.

Relative pages
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  • Learn about the WiFi interferences to the human body
  • Learn about the origin of Internet, how it started and the course to what we know today as Internet
  • How to make a MAME arcade machine controller without the use of a keyboard
  • Re-use and/or extend your molex connectors

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  • At 2 November 2011, 5:56:38 user Kammenos wrote:   [reply @ Kammenos]
    • @Roger Cole for small signals you may wanna use RJ connectors, like the ones used on telephones and ethernet cables. They come in different sizes with 2,4,5,8 wires and they are pretty small. This is what i would use for small signals. For high current rates, polarized headers such as these are ggood:

  • At 1 November 2011, 17:24:02 user Roger Cole wrote:   [reply @ Roger Cole]
    • Great resource as has been said. I am looking for a plug/socket to adapt a six-wire 12v house thermostat controller. Based on reading this, (a) I can forget about using the ATX 6 pin as being too rare but (b) looks like I could use two peripheral 4-pin plugs or (c) the PCI Express 6=pin. The latter looks like overkill for the small signals and currents there will be and I am thinking option (b). Any thoughts appreciated!

  • At 20 October 2011, 5:13:55 user Kammenos wrote:   [reply @ Kammenos]
    • @Mark Green each connector has a different key, so that they cannot be connected wrong. You may wanna check the keys to ensure that they do connect there. If you see closely the conneters you will notice that each pin may be rectangular, or like a roof top. The same "keys" applies to the the connector receptacles on the motherboard. This way, you cannot put wrong connectors.

  • At 19 October 2011, 20:20:57 user Mark Green wrote:   [reply @ Mark Green]
    • What a great resource!

      MY Gigabyte x58 has and 8 pin MBD connector which is labeled \"ATX\"-no mention of pci-e.

      Can the 6x2+2, or 6x2 pci-e cable from the P/S be plugged into this?

      The OCZ power supply I want to buy does not mention 8pin ATX, it only talks about 6x2 and 6x2+2

      I am guessing the \"ATX\" 8 pin receptacle on the MBD has 12v conductors in the MBD which lead to the pci-e slot?

      I am confused-can you explain?
      Thank You!

  • At 21 February 2011, 2:56:29 user Pietro Azurin wrote:   [reply @ Pietro Azurin]
    • You have a very clean, sharp and down to earth site. Keep-up the hacker/hobbiest point of view audience. I learn so much from your site.Thanks

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