Missing wire/pin in 20-pin connector?

[elscorchoz]

So I just received a Corsair CX430(v2) PSU from newegg, the first part in my new rig (first homebuilt in ~10 years). I plugged it up to my old comp and it failed to start, I removed it and noticed the 20-pin connector (the main connector to motherboard) is completely missing one of the wires/pins... Is this normal?

It wouldn't surprise me if its supposed to be like that, I just noticed my old psu has all 20 wires/pins and thought maybe this is why the CX430 is failing to power up my old computer.

 

[hunter315]

The missing wire was formerly used to provide -5 V power to the motherboard, that was only used by old boards for ISA slots, any board with no ISA slots has no need for -5 V power, and any PSU designed since about 2005 won't even be producing -5 V power so it has nothing to connect to that slot.


How old is your old computer? It would have to be really really old for this to be an issue for it. Do any fans spin at all? You may have a DOA PSU, but wait for the rest of the parts to get their so you can check it in the system.

 

[delluser1]

-5v was removed from the ATX spec recently , before that it had been an option for years, it's normal for a modern psu to be missing a pin
http://www.playtool.com/pages/psuconnectors/connectors.html#atxmain24

Too slow

 

[elscorchoz]

Thx for quick response. The old computer is from ~2005-2007. It runs fine on its generic psu.
With the CX430 on powering: the PSU fan runs, the CPU fan runs but barely (usually on startup CPU fan throttles to full speed then calms back down), motherboard LED comes on, Mouse lights up, but no post.

 

[elscorchoz]

Best answer selected by elscorchoz.