Asked by: Maybell Dulisz
technology and computing computer peripherals

How do you wire a 4 wire fan?

Last Updated: 23rd June, 2020

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Then, why do computer fans have 4 wires?

In addition to the power, ground, and tach signal, 4-wire fans have a PWM input, which is used to control the speed of the fan. Instead of switching the power to the entire fan on and off, only the power to the drive coils is switched, making the tach information available continuously.

Additionally, why do PC fans have 3 wires? The three-wire connectors are for small chassis fans with lower power consumption. The four-wire connectors are for processor fans with higher power consumption. A three wire fan reports its speed. Add a fourth wire, and the fan's speed can be varied by the motherboard.

Likewise, people ask, how does a 4 pin fan work?

A 4-pin fan is designed for control a different way, by giving it a fixed voltage supply and then a special signal called PWM on Pin #4. The 4-pin fan has its own internal circuit to apply that PWM signal to its power supply to adjust its speed. This means of control is called "PWM Mode".

How do you wire a 4 wire to a 2 wire?

The ground may be there, but it may not be connected.

  1. Take the ends of both the 12-2 ROMEX® wire and the 12-3 ROMEX® wire and strip 1/2 inch of insulation off each wire. Push both ends into an electrical junction box.
  2. Look at the four wires of the 12-3 cable.
  3. Alternatively, use the red wire as the hot wire.

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Adosinda Donovan

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Are computer fans AC or DC?

Now if you mean a computer fan, well, the answer is more complicated. They require DC voltage to run, but the motor itself is really a 3 phase AC motor. Small 120Vac (or 240Vac for Europe) fan motors are often just capacitor run AC motors or split phase AC motors. Really small AC fans use shaded pole motors.

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What is the difference between a 3 pin and 4 pin fan?

What's the difference between 3-pin and 4-pin fans? 3-pin fans, or "DC" fans, are typically worse than 4-pin fans when changes are made to the voltage in order to adjust the speed of the fan. Changes can easily cause the fan to stall or modulate erratically if the voltage isn't correct.

Dong Zhuan

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Can I connect a 3 wire fan to a 2 wire connector?

The 3 Pin fan will fit onto the 2 pin you just need to match the holes and the pins and see which two contacts make the fan function.

Candance Todriya

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How does a computer cooling fan work?

A computer fan is any fan inside, or attached to, a computer case used for active cooling. Fans are used to draw cooler air into the case from the outside, expel warm air from inside and move air across a heat sink to cool a particular component.

Erradi Moeller

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What are the 4 wires on a computer fan?

The fan has 4 wires (yellow, black, white, red) but the power supply has just two wires.

Charlotte Barga

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How does a 3 wire fan work?

In a 3-wire fan, first two wires are the power supply wires of the fan. The third wire, comes directly from the output of the built-in 'Hall Sensor' chip generates output pulses during the fan rotation. With the help of this third wire, a monitoring circuit can 'see' the rotation.

Valeri Ermisch

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Can 3 pin fans work on 4 pin?

Apparently a 3-pin fan can plug directly into a 4-pin socket. Two of the pins provide power to the fan, the 3rd provides an RPM pulse to the motherboard to read the speed. The 4th pin is for PWM speed control. If you plug a 4 pin fan into a 3 pin socket, the fan speed will be controlled by voltage and it'll still work.

Alline Andresch

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Sem Calle

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What is the yellow wire for on a computer fan?

THe yellow wire sends a signal to the motherboard to monitor RPM. resistor or using a fanbus.

Kbir Stammberger

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Can I use a 3 pin fan for CPU?

Yes, you can also plug a 4 pin fan into a 3 header.. You can plug a 3-pin fan into a 4-pin header just fine. Speed control options (RPM range) will vary between fans and motherboards on a 3-pin connection, but the fan will spin.

Siny Mayench

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How do I reduce the fan noise on my computer?

Low-cost methods
  1. Reduce CPU supply voltage ("undervolting").
  2. Enable Cool'n'Quiet for AMD CPUs or SpeedStep (also known as EIST) on Intel CPUs.
  3. Reduce fan speed.
  4. Mount fans on anti-vibration mounts.
  5. Remove restrictive fan grills to allow easier airflow, or replace noisy fan grills with quieter versions.

Margarita Kamoniewsk

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Can you control speed 3 pin fan?

The speed of BOTH 3-pin and 4-pin fans can be controlled, but the method is different for the two types. For 3-pin fans, the connections to it are Ground to Pin #1, +VDC (varying) to Pin #2, and Speed signal on Pin #3.

Jiao Hasselbusch

Reviewer

What is the fourth pin of a fan header used for?

A four pin connector is a little different than the three pin connector since it has the extra (fourth) wire used for controlling and sending signals to the fan, which likely has a chip on it that tells it to slow down or speed up (in addition to the other wires the three pin connector has).

Ayada Sophia

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Are all 4 pin fans PWM?

All 4 pin fan headers are NOT PWM.

Djeneba Chanov

Supporter

Do I need PWM fans?

PWM usually merely offers increased functionality ranges (some going as low as 20%). but no. you really don't need PWM for case fans. whether or not you want better case fans is up to you, but to make that decision solely on using 3 pin or 4 pin fans is largely irrelevant.

Nain Zgoresk

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Can 3 pin fans be PWM?

With the 4-pin PWM to 3-pin transformer, all 3-pin fans can now be controlled with a normal PWM signal. The converter is connected to your motherboard or PWM fan control, while the fans are connected to the converter. Now your 3-pin fan can be controlled like any other PWM fan.

Matvey Belgibaev

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How do I connect 4 pin fan to Molex?

To use a Molex will require a 4 pin fan to 4 pin Molex adapter. The 4 pin fan cable will plug into this adapter. You only use 2 wire when plugging into a molex, the black(negative) and Yellow(12v Positive) from the molex.

Zinayida Vilajuana

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Does motherboard control fan speed?

The motherboard WILL NOT control your fans by itself. Give the software a go.

Victor Jonassohn

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How many fans can a motherboard fan header handle?

Using two parallel fans via splitter on a single motherboard fan header will draw twice as much amps as a single fan. If your fans are each 0.64A @ 12V, using two fans on a single motherboard fan header will draw 1.28A @ 12V, not 0.32A @ 12V.