I'm working on building a computer (first time for me). There are several plugs that I need to connect to the motherboard (Power LED, reset switch, etc). Of the two wires, they are either:

  1. Color and white (reset switch, power LED, HDD LED)
  2. red and black (speaker, power switch)

The manual for the motherboard has a nice diagram of where to plug them in, but has them labeled + or -. Which colors are positive, and which are negative?


For reset swtich and power switch, it does not matter.

By electrical convention, red is positive, black is negative. For the others, generally I think colour is positive, white is negative.

For the connections you have listed, you will not damage your system if you connect them up backwards; the lights simply won't work.

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    Thanks! It's good to know this won't damage anything. Being new to computer building, it's hard to know what parts I need to be really careful with, and I can relax about. – David Oneill May 3 '10 at 13:58
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    My motherboard manual specifically urges to take notice of the + and - to plug the power and rest switches, whereas you say this does not matter. Why would the manual say differently? – Félix Gagnon-Grenier Nov 5 '17 at 10:51
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    @FélixGagnon-Grenier I can offer no electrical explanation. Switches break or make an electrical connection. They don't have polarity. Perhaps the advice is in a context that would include the LEDs? – RJFalconer Nov 6 '17 at 9:58

In most motherboard cables there is a little triangle that marks the positive side. See the picture below:

Motherboard cable positive side

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    Ah, that's good to know. It's likely this is a new thing, since I would have noticed those. A lot can change in motherboard design in 4 years! – David Oneill Oct 7 '14 at 21:16
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    Just a general thought, why didn't they just use a plus sign instead of a triangle? – Hind-D Oct 14 '15 at 20:23
  • @Hind-D yes indeed, I have a Thermaltake F31 Supressor (great case btw) and most connectors have + / - on them, except the PW and RESET switches that oddly have the triangles - well we learn something everyday ! – MemeDeveloper Apr 6 '16 at 15:41
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    @Hind-D that'd be wayyyyyy too simple – Félix Gagnon-Grenier Nov 5 '17 at 3:45

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