How to Control the Computer Fan

By Chase Hasbrouck

Some computers sound like jet engines. Their fans run at full speed, all the time, which makes it uncomfortable for users to work on that computer. Other computers have normal fan speeds, but are still too loud to be used in environments that demand quiet (such as a home theater). Many manufacturers today allow the user limited control of fan speeds via the computer's Basic Input/Output System (BIOS), but a better choice is the program SpeedFan, which gives the user fine control.


Step 1

Open Speedfan. The program will automatically scan your computer's hardware, then display its readings.

Step 2

Select "Configure" to open the Speedfan configuration tool. Choose the "Fans" tab.

Step 3

Click the check box next to each fan you wish to control, then click the "Speeds" tab.

Step 4

Set the minimum and maximum RPM values for your fans. (These values are in percentages, so 100 percent is full speed, 0 percent is stopped). Once set, check "Automatically variated" and click "OK." Speedfan will begin controlling your fan's speed.

Basic Input/Output System

Step 1

Restart your computer, and press the specified key to enter your computer's "BIOS SETUP" mode. (The specific key differs depending on your brand of BIOS. Dell BIOS's, for example, use F2).

Step 2

Find the menu in your BIOS labeled "SMART Fan," and select it.

Step 3

Edit the settings in the "SMART Fan" menu until your fan reaches the desired speed. You should see an option for "PWM value." This specifies how much voltage to provide to the fan, which changes its RPM.

Tips & Warnings

  • Only certain BIOS's and certain fans are user-controllable.

References & Resources