The heat sink plays a role in cooling the computer. Whether it is the CPU, graphics card, chassis, or power supply, it needs a cooling fan for auxiliary cooling. Today, let's talk about the fan interface. The types of cooling fans are divided into two pin, three pin and four pin. Today, the home of installation mainly shares the difference between the two pin, three pin and four pin cooling fans. Let's have a look!
2-pin cooling fan (simple structure, but unable to measure speed)
The 2-pin cooling fan means that it has only two power cords, red and black. The structure is very simple. One is used for power supply and the other is used for grounding, but it has no speed measurement function. At present, 2-pin cooling fans have been widely used in the market, but 2-pin fans can no longer meet the requirements in terms of speed change, and 3-pin and 4-frame fans are more appropriate.
3-pin cooling fan (VC voltage speed regulation, poor flexibility)
The 3-pin cooling fan interface is mainly a yellow or black yellow green line added to the red and black power lines, which is mainly used to measure the speed. The motherboard can detect whether the fan is rotating and what the speed is. However, the 3-pin cooling fan speed regulation is achieved by adjusting the fan voltage. In addition, whether the motherboard can adjust the speed depends on whether the motherboard supports it. Obviously, this speed regulation is not flexible enough, The CPU status information cannot be reflected in real time, and various settings need to be made in the motherboard BIOS.
More importantly, different fans also have different starting voltages. The voltage speed regulation is not linear. Controlling the speed through voltage may lead to the failure to reach the required starting voltage of the fan when the voltage is low, and the fan will stop running.
4-pin cooling fan (more flexible and intelligent speed regulation)
The 4-pin cooling fan has another PWM line (pulse width modulation) on the basis of the 3-pin cooling fan. The so-called PWM line uses the PWM mechanism to adjust the fan speed, while the fan voltage is constant, which avoids a series of disadvantages of controlling the voltage to change the speed. The PWM fan does not need to rely on the motherboard BIOS, which is more convenient. PWM pulse signal can output different duty cycles, and 0-100% duty cycles can adjust different fan speeds, so it can achieve accurate and flexible control.
