Some motherboards will have a Smart Fan Mode feature in the BIOS.

Again, the option displayed will be different according to the motherboard manufacturer.

Search for a Fan Speed Control option.

Once inside the BIOS, use the arrow keys to navigate through it.

(If you do not know how to enter the BIOS, please refer to the user manual for your laptop/motherboard).

To enter your motherboard’s BIOS, press the Del or F12 key rapidly.

This is because the RPM, by default, is set to maximum on your BIOS (Basic Input/Output system). Sometimes, the fans on your computer will spin at their maximum RPM. If you have connected the fans to your motherboard, you can easily adjust its speed with the help of the BIOS. Controls From BIOSĪny piece of hardware attached to a motherboard will have settings in the BIOS to control it. Here are a few techniques to change/control the fan speeds. We need a Molex to 4-pin PWM hub to control its speed. Fans connected with this cable also spin at maximum RPM.

Molex Fan Connector connects the fan to your PSU (Power Supply Unit).

However, it uses the sense pin to control the RPM according to the CPU load.

4-pin Pulse Width Modulation (PWM) is also connected to the motherboard.

Fans connected with this cable spins at maximum RPM unless we change the speed from the BIOS.

3-pin DC fan connector cable connects the fan to your motherboard.

You can find three types of cables that connect the fans to the motherboard/power supply.

Depending on the cables attached, the fans on a desktop PC are connected either to the motherboard or the power supply.

How Does a Computer Change the Fan Speed?įirst, let’s discuss how a computer controls its fan speed. However, you can control your fan speeds according to your needs using third-party applications or tweaking fan settings on your BIOS. If you are doing some CPU-intensive tasks, your CPU cooler will spin at a higher RPM (Rotations Per Minutes). A computer adjusts its fan speed according to the load it gets.

Laptop fan speed control