Anyway to make my PWM fans spin even slower?

Goose · 24 Jul 2015 at 11:00

I currently 5 Akasa Apache's in my PC connected to a Phobya PWM hub and at their lowest setting on my motherboard they spin at about 1000rpm and at idle i still find this to be a little louder than my OCD noise freak meter can take.

I was wondering if there was a way to make them spin even slower at idle without having to buy a fan controller. I like to have my case looking nice sleek which basically means nothing in the optical drive bays.

Thanks

C64 · 24 Jul 2015 at 11:15

Pwm fans have a pwm hard programmed in like mine are 900-1200 rpm.

If you change to voltage controlled instead of pwm they will spin slower and ramp to full speed when cpu under load

Mine on voltage controlled via bios spin at 600rpm and full speed under cpu load, depends on bios im not familiar with as rock features.

Could try 5v or 7v adapters on each fan just to have them permanently sit at slower speeds too.

If I were you i'd run it all voltage controlled case fans and only pwm on the cpu fans.

Goose · 24 Jul 2015 at 11:43

As far as i can tell the motherboard I have only allows for them to be under pwm control or fully on

It would be idea to have a setup like yours, 600rpm at idle and full speed under load.

Tealc · 24 Jul 2015 at 11:59

You could try dropping their supply voltage below 12v but still use their pwm function. My Apache fan was not very good at voltage control and stalled at around 8v anyway so I replaces with a decent fan.

Goose · 24 Jul 2015 at 12:26

Tealc said:
You could try dropping their supply voltage below 12v but still use their pwm function. My Apache fan was not very good at voltage control and stalled at around 8v anyway so I replaces with a decent fan.

Would that be done with a resistor cable of some sort? Which fans did you replace them with out of curiosity?

badbiddy · 24 Jul 2015 at 12:47

Noctua sell LNA cables (low noise adapter) that basically just kills a bit of the voltage.

new boy · 24 Jul 2015 at 12:53

Have you tried using the ASRock Fan-tastic utility?

With that, it will test the fans and you can then set fan curves.

It even lets me put them down to the point when they stall and stop for me.

Tealc · 24 Jul 2015 at 13:04

Goose said:
Would that be done with a resistor cable of some sort? Which fans did you replace them with out of curiosity?

Yes maybe something that'll go down to 9v or so. I think there are a few commercially available solutions.

I replaced mine with a Noctua NH-something12 (a 3 pin fan) and control it using PWM via one of my PWM converter circuits. It can go down to around 300RPM without too much bother.