This variation in heat dissipation often leads to questions on cooling fans and their speed. When you are working on a laptop, you might observe variations in the heat produced. Here, we discuss two types of cooling fans- Pulse Width Modulated (PWM) fans and DC fans. They also aid the working of heat sinks by distributing air across them. The fans in computers gather cool air from the ambient and expel the warm air outside. All computers have built-in fans, as they are one of the approved cooling mechanisms for processors. The PWM signal is the control input of the PWM fan.Ĭooling fans are a vital part of computer hardware, as they cool the CPU and ventilate casing, enabling active cooling in computers. PWM fans are 4-pin fans, where the fourth wire sends a PWM signal to the fan motor.

PWM fans are DC fans with an extra wire for PWM. These fans are also called 3-pin fans, as they come with 3 pins: a supply pin (usually 12 V DC), a ground pin, and a signal pin. Cooling fans are a vital part of computer hardware, as they cool the CPU and ventilate casing.ĭC fans are supplied with DC power from regulated DC supply or motherboard header pins.

Good fan speed for pc