What are the 4 wires in a PWM fan for?

[rubez]

Hi, I need to know what the 4 different wires on a Noctua PWM case fan are.

There is black, yellow, green & blue.

What are each?

Thanks.

 

[uplink-svk]

I've seen many Noctua fans in my life, but never colored wires, can You please be more particular, or photosnap what You mean?

 

[nullifier]

Pin Function Wire Color:
1 GND Black
2 12 V Yellow
3 Sense Green
4 Control Blue

Source: Section 4.1.6: http://www.formfactors.org/developer%5Cspecs%5Crev1_2_public.pdf

 

[uplink-svk]

nullifier - since all cables on noctuas are sleeved, never managed to notice them 😀...now I pushed up sleeve of few noctuas on my table 😀

 

[rubez]

Thanks. I am tring to change my PSU fan with a Noctua one.

Noctua has 4 wires, PSU has 2.

I can either cut and solder the wires.

or maybe, could I transplant the black/yellow pins from the Noctua into the 2-pin header connector of the old PSU fan? (therefore no soldering)

Is that a possibility?

What do you suggest?

 

[nullifier]

To be honest rubez I haven't transplanted anything like that in a PSU before, but since it is just a fan transplanting the black/yellow pins in the old PSU fan header seems like it work to me. The only concern is that header doesn't actually have the amperage and voltage to push the new fan. If it is undersized then it may not work at all. I have had that problem with fans on a radiator that required too much power and the mobo pin header couldn't push them without external power.

That being said, I am still not 100% of the potential problems you might face so perhaps that is question for someone else who has done that before in a PSU I just can't be certain that my experience will translate here.