Changing my 80mm SanCool fan in a Antec HCP 1200W PSU with a Noctua 80mm PWM fan

[FlipFilm]

I am changing my 80mm SanCool fan in a Antec 1200W PSU with a Noctua 80mm PWM fan.
Old fan has black, red, yellow and brown wiring.
Noctua has black, yellow, green blue wiring.

Found out that black and yellow on Noctua is +12V, green is rpm and blue is pwm signal.

http://www.noctua.at/main.php?show=faqs&step=2&products_id=43&lng=en#6

Only problem is I do not know what the yellow and brown wires do?
I tried to connect the yellow from SanCool to the green rpm from Noctua and the brown mysterious wire to the blue Noctua wire.

Result is:
The Noctua fan never spins..
It starts for 1 sec at boot and then stops and never spins again until thr next boot.

Any suggestions?

(why do I have to change the psu fan you ask? Because it had become old and noisy I say)

Regards,
Daniel

 

[ganon11000]

Do you have a digital multimeter?
If you do you can test the voltages of the wires and find out which ones are + and -. When you do, wire those in. I would assume the speed control is PWM but it might be a propitiatory thing and not compatible with your replacement fan.