However, checking it is not enough to properly set it up, though it would be nice if things were this easy! For now, you can check it, but nothing will happen – you shouldn’t notice any change in your fans’ speeds.Ĭlick on “Configure” to bring up the options window.

On the main SpeedFan window, you may have noticed a checkbox for “Automatic fan speed”. If you want to control the speed of your 4-pin fans, you’ll have to use some sort of fanbus or external fan controller. This is because SpeedFan controls fan speeds’ by varying the output (using PWM) of the 3-pin fan headers on your motherboard. (Some motherboards already support this, but SpeedFan brings this functionality to almost any motherboard that’s reasonably new)įirst and foremost, the fans that you want to control must be plugged into one of your motherboard’s 3-pin fan headers they cannot be plugged into 4-pin molex connectors that come straight from your power supply. SpeedFan has a lot of functionality and it’s easy to get lost in all of that when all you want is something simple like automatic fan control. However, it does require some configuration, as I’ll attempt to show you in the following article.Īll the material I’m about to present here is available in the help file for SpeedFan, however, since most people use the Internet for everything, myself included, I thought I’d summarize the most important points. This can allow you to find the right balance between a cool system and a noisy one.

As its namesake implies, SpeedFan is able to automatically control your computer’s fan speeds based on the temperatures reported by various hardware sensors. Besides being able to show the temperatures inside your system (from various sensors in the CPU, motherboard and HDDs) and other vitals such as voltages and fan speeds, it can also automate the cooling cycles of your machine. SpeedFan is a great utility for enthusiasts who’ve built their own PC.

Control case fan