How do wire up a computer fan?

[magicstix]

How do wire up a computer fan?

I've got 4 wires red, black, blue, white. Red and black make mach 1 air flow. Blue and white don't seem to do much. Help?

[low277]

The black + red are the dc power to the fan, I believe that the blue + white are for speed control and feedback.

Did the fan come out of a piece of equipment?

[kfk]

If the fan has 4 wires, it is a PWM controlled fan.

Wiring is as follows:

Pin Function Wire Color

1 GND Black

2 12V Yellow

3 Sense Green

4 Control Blue

These colors are Intel design standards, but your wire colors are slightly different. The wire on pin #3 is the RPM sensor, and the wire on pin #4 is the PWM control input.

A PWM fan will operate at 100% if no control signal is present on pin #4.

Connect the wire from pin #2 to +12V, and the wire from pin #1 to ground. The fan should run at 100%.

[magicstix]

it's probably out of a 94' computer I had. It's about 4 1/2" fan, Delta is the brand.

The other fans I've put in ice shack before run a normal speed with red/black hooked up.

How do they control rpm with control pin? How many volts?

Right now if I use red/black it'll look like were moving at 70mph across the ice and it's in a perm. house, stationary.

[magicstix]

So I just messing with fan and accidently bumped the blue and white together and fan speed reduced in half. I can live with this speed but what is it doing to motor or does increase amp draw?