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I am building a new PC and I haven't done this in a few years. It will have all the latest tech stuff. I got my PSU in the mail and I am looking over the cables (it has a lot) I thought it was a modular PSU so I could only use the cables I need but instead it is a hybrid (some wires attached and some can be added/removed instead of all of then being removable).

  1. So I am curious, I believe all my hard drives and optical drives are powered off of a sata power cable so does that mean I probably do not need any of the 4 pin molex cables? Or are these used for other things?

  2. I know the 24-pin cable goes to my motherboard.

  3. I have some 6-pin cables that are labeled pci-e which is new to me. I read these are for some grapghic cards and stuff. I have 2 grapghic cards but they do not require a seperate pci-e power wire be hooked to them. So are these pci-e wires just to power pci-express cards? Or for other things as well?

  4. I have a 4pin ATX 12v wire, what is this for?

  5. 8 pin EPS, what is this for?

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up vote 2 down vote accepted

1) Molex cables are used by fans in many cases.

3) Many newer graphics cards require those PCI-e cables. I've yet to see any other hardware that uses them, but I believe they are only compatible with PCI-e hardware that expressly supports them.

4) Some motherboards require these to power the CPU.

5) This has the same purpose. Newer motherboards will use these as opposed to the 4 pin ATX 12v wire.

If you don't have anywhere to plug these cords into, don't worry about them--if there's not a hole for it, the motherboard doesn't need it.

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Molex connectors can also be used for other computer accessories, like cold cathode lighting - the UV lights look really cool in a case with UV-reactive cables and such (I have too much fun with my PC) – Jared Harley Apr 17 '10 at 1:04

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