Controlling rpm on 3pin Fan

[RemyXIII®]

I have a 3 pin fan and no option to use DC instead of PWM in my motherboard's BIOS. What options do I have for controlling it? Before anyone says to just buy a 4pin fan, I have a ton of unused 4pin fans but prefer to use this one due to aesthetics and how it matches my build. The fan is a solid aluminum Evercool that is stunning with my hand built aluminum open frame.

The fan runs at 2400rpm and is way overkill (so loud) for all but the hottest running games.

[Brimac]

lots of ways, what is your motherboard? there is software , fan controllers, inline resister.

[Bad 💀 Motha]

Control it inside your OS with software.

[_I_]

3pin is voltage control/dc, not pwm
in bios, most headers have setting for dc or pwm

what mobo?
brand/model?

but many oem boards have lots of options locked out

[Bad 💀 Motha]

Setting to PWM wouldn't do anything extra for a 3-pin Fan, as explained above.

[RemyXIII®]

ASRock Phantom Gaming B760i Lightning ITX

I figured out why there is no DC option. It appears the MB knows to set it to DC or PWM automatically. I'll play with it a bit more because I could swear the fan ran at 100% despite the fan curve I was trying to set.

[Bad 💀 Motha]

Some motherboard BIOS does allow you to set an RPM range for 3pin fans.

Best bet is if they are not PWM, set to DC for 3pin and then use OS software to manually control those 3pin fans allowing you to pick a specific RPM in that software. However when outside the OS or not running that software, it will abide by how the BIOS handles it.

[_I_]

dc doesnt always use %, but voltage,
as 50% pwm will limit the fans speed to half, but with dc control 12v is max and 6v would be near stopped

[Bad 💀 Motha]

I understand it does all of that by Voltage. Your BIOS or OS based Software showing a Fan RPM # Value or Fan Speed % is just a method of being "user friendly" as these software and such don't have you picking voltages or voltage ranges do they; no, they never do that.

PWM has more options, as you can have it following a fan curve based around Temp (*C) or have it following a fan curve based on CPU Load %

[_I_]

both should do that, but the scale would not be the same
pwm is linear 0-100%, dc is not ~8v-12v but not a line depending each fan

[Electric Cupcake]

I use a fan header hub that slaves (or whatever the polite term is now) all the fans on a chain to the speed of the single 4-pin one at the top.

[Brimac]

Asrock has motherboard utility to controll fans in os. If using bios look for apply button before saving bios and reboot.

[Bad 💀 Motha]

Most BIOS don't have an "Apply"
That IS what "Save & Exit" does.

[Brimac]

when setting fan curves in my gigabyte board i have to hit apply in bios for it work,before save and reboot. he said it was not working after reboot. may not apply for asrock though.
smartfan5 in my bios

[Electric Cupcake]

Originally posted by Bad 💀 Motha:

Most BIOS don't have an "Apply"
That IS what "Save & Exit" does.

That's a bit pedantic. If we're going to split hairs, one might point out that "bios" isn't used anymore because it's "UEFI" now.

[Bad 💀 Motha]

UEFI is just a type of BIOS (Legacy vs UEFI); it's still just the BIOS.