How to undervolt 3-pin fans?

[Shaqalac]

Hi LTT,

 

I have some Gentle Typhoon 1850 lying around and I wan't to use them in my case. However, I really need to undervolt them, as I don't want them to run at full speed.

 

What is the easiet way to do so?

 

Cheers

[iRileyx]

Assuming you can connect them to motherboard headers, you can download speedfan and use that.

If theyre on Molex you'd need a molex fan controller, if you can't get one of them they'd have to be powered from the power supply, and that'd mean you can't adjust the speeds.

[historicalpoultry]

There's also Molex to 3pin adapters that let you run the fans at fixed 5 and 7 Volt speeds if that's what you're looking for.

[Shaqalac]

How would something like this work: https://www.coolerkit.dk/shop/3-pin-kabel-2032p.html

 

Fine I imagine but could I run into problems when the fans are running on top of a radiator (no speed control)?

 

My case only has a CPU and Chassis fan header (2 in total) so when having a total of 4 fans (3 case and 1 cpu fan) I'd need a splitter. If I connect all 3 case fans to a splitter and control them via SpeedFan, they will all run at the same speed all of the time right?

 

[LogicalDrm]

On 9.2.2017 at 1:39 PM, Shaqalac said:

Fine I imagine but could I run into problems when the fans are running on top of a radiator (no speed control)?

 

Thats hard to say. Running them at 5V versus 12V will have effect on cooling performance.

 

On 9.2.2017 at 1:39 PM, Shaqalac said:

My case only has a CPU and Chassis fan header (2 in total) so when having a total of 4 fans (3 case and 1 cpu fan) I'd need a splitter. If I connect all 3 case fans to a splitter and control them via SpeedFan, they will all run at the same speed all of the time right?

Yeah, thats the way it works. There's also third option. You can get hardware fan controller. There are two types, ones with knobs and ones with software. With knobs include those for 5.25'' bays which use thermal probes and claim to have accurate control over temps.

 

Essentially knob-controller allows you to change voltage between 5V and 12V. It might be good choice if you are worried about performance on 5V.

 

Software capable controllers, aka NZXT Grid+ v2 and MSI Commander Mini (if there are more, do let me know for future), can have individual controls for each fan with curves. They are connected with USB and so they use same sensors with monitoring software.