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Difference between CPU 8-pin and GPU 8-pin?

Discussion in 'General Hardware' started by Trackr, Dec 20, 2011.

  1. Trackr New Member

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    I need both an 8-pin GPU extension cable and an 8-pin CPU extension cable.

    Problem is, I can't tell them apart, and no website correctly identifies which one they're selling!

    Any help? :(
     
  2. scaminatrix

    scaminatrix

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    Search for "12v EPS Extension" to find CPU extension cables, and
    search for "8-pin PCI Express Extension" to find GPU cables

    These are the identifiers, if you're not comfy with trial and error then just use these :)

    CPU

    GPU

    If you link to your preferred e-tailer, I'll help you identify them if you like?
     
  3. Arctucas

    Arctucas

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    Molex technical drawings:

    EPS-http://www.molex.com/pdm_docs/sd/039012080_sd.pdf


    PCI-E-http://www.molex.com/pdm_docs/sd/455870002_sd.pdf (third generation polarization)

    Notice the difference in the keying.
     
    Last edited: Dec 20, 2011
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  4. Athlon2K15

    Athlon2K15 HyperVtXâ„¢

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    cpu 8pin has 4 power 4 ground 8pin gpu has 3 power 5 grounds
     
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  5. xaira

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    an 8 pin pci express extension is for the gpu

    an 8 pin EPS exension is for the cpu
     
  6. cadaveca

    cadaveca My name is Dave

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    Not exactly.

    8-pin GPU has 3x12v, 3x ground, and two "sense"/ground. ;)

    Meanwhile, 6-pin GPU has 3x 12v, 2x ground, 1x sense/ground.

    pcie_plugs.jpg



    A CPU 8-pin has 4x 12v, and 4x ground.


    Each has 12v on "opposite" pins, and are keyed differently, so confusing the two should be pretty easy...8-pin PCIe plug inserted into 8-pin CPU receptacle should be very hard to do, and vice versa.

    Anyway, if you look at the plug itself, and where the clip is, you can determine which is one. One has 12v lines near the clip, the other does not. CPU plug has 12v near the clip.


    :rockout:
     
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  7. Arctucas

    Arctucas

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    Which is easy if your PSU has colored wires.

    My PSU, on the other hand, has ribbon cables, which makes identifying a given individual conductor impossible by merely looking at it.
     
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  8. cadaveca

    cadaveca My name is Dave

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    OK.

    Then:

    Clipside pins...square plugs on outside 2 plugs= GPU, square plugs on inside 2 plugs = CPU.
     
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  9. Arctucas

    Arctucas

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    No.

    [​IMG]
     
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  10. cadaveca

    cadaveca My name is Dave

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    Ha. Whoops. Weird. The drawings by Molex above and my cables for the CPU are the same as the Molex drawing, so I assumed the drawing for the GPU plug was right too. I guess there's more than one type of connector, or something. :eek:


    Anyway, that's a GPU 8-pin in that pic. The two boxes on the right are joined together to prevent insertion into CPU 8-pin plugs(modular 6+2 conector should have that as well).
     
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  11. Arctucas

    Arctucas

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    On the Molex drawing I referenced, there are three generations of this connector. The third generation is the one:

    [​IMG]
     
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  12. DaMobsta New Member

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    If it helps, if a connector is a 4pin+4pin then surely it's for the CPU. If it's 6pin+2pin then it's pcie. That is if you can get connectors that are designed like that :)
     

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