Could an Arduino be used to control fans?

[star_pilot475]

So I had this crazy idea...could you use an arduino to control fan speed and all that? My motherboard doesn’t have any 4 pin connectors so could this be a crazy and janky option to control fan speed? 

[NinJake]

I'm sure it could work. Here's another project which is similar. https://www.raspberrypi.org/forums/viewtopic.php?t=130213

Make it happen!

[lieder1987]

Might be cheaper and easier to find / buy a motherboard that has 4pin headers....

[.Apex.]

36 minutes ago, star_pilot475 said:

So I had this crazy idea...could you use an arduino to control fan speed and all that? My motherboard doesn’t have any 4 pin connectors so could this be a crazy and janky option to control fan speed? 

You definitely can, but it's probably much easier to connect a variable resistor instead to control speed, that's how manufacturers do it with their "Low-Noise adapter", which is basically an adapter with a resistor on it to drop the voltage

[NinJake]

Keep in mind if you do any DIY you'll have to either find a way to pull the temperature data to ramp the fan speed accordingly or you'll simply have static RPM fans anyways. I'm just not too sure how easy it would be to pull the board temperature data and import it into your arduino/pi. If you do this you should totally document the project!

[HanZie82]

Yeah should be pretty easy. But you would need a temp sensor or a lot of programming knowledge to pass trough the onboard temp sensor to the arduino.
And a 12V fan you can just use the 3rd PWM cable (together with ground ofc) to controll the speed and use the computers PSU for the 12V for the fan.
Since Arduino only works on 5V.

Also if its just to have a 12V fan run more quiet, just connect it to the 5V of the PC, and it might still work but more silent and slow.

If normal colors on the PSU yellow is 12V+ and red is 5V+ Black is ground.

[star_pilot475]

Thanks guys! I’ll see what I can do!

[Mira Yurizaki]

5 hours ago, star_pilot475 said:

So I had this crazy idea...could you use an arduino to control fan speed and all that? My motherboard doesn’t have any 4 pin connectors so could this be a crazy and janky option to control fan speed? 

Funny thing, this was my senior mini-project. Though we used a PIC8 microcontroller.

 

The only problem is if you want it to be automatic, you'll have to add in a thermal probe. Though you could also probably use a Windows based app to control it over a serial port and use values based on what the OS can get you.