[SOLVED] 3pin case fan always running at 2500+ rpm

[Lazy Dog]

My motherboard is a A320M-a pro max, it only has 1 4-pin system fan connector. Setting fan to DC or PWN on BIOS and/ enabling Smart Fan/ change fan curve does nothing.
Do i need a 4pin case fan?

 

[Lutfij]

DC or PWN
PWM

Can you mention the make and model of the fan used? Also, if you've got the fan connected via a hub or splitter, that would be of assistance to us. Mind also sharing an image of how you've got the fan connected to the motherboard? Per your motherboard manual, page 15, that SYS_FAN header will cooperate with 4pin and 3pin fans. As a side note, what BIOS version are you currently on for your motherboard?

 

[Lazy Dog]

I'ts just a generic 3-pin DC case fan connected to the 4-pin motherboard system fan connector. The connectors fit properly with the little plastic thingy they have.

I'ts probably 5+ years old, but it works fine.

BIOS : American Megatrends Inc. 2.80, 7/12/2020

 

[Lazy Dog]

Nevermind, I found this. Apparently even though the BIOS shows the options my mobo doesn't support DC fan control:

MSI Global English Forum

...

forum-en.msi.com

 

[Paperdoc]

Look again at Lutfij's post. p.15 of the manual does NOT say anything about DC Mode, that's true. BUT the screen shot DOES show a little circle on the left for "PWM" that is lit up. Click on that to UN-choose PWM Mode, and MAYBE that will set DC Mode.

 

[Lazy Dog]

Thanks, but the screenshot was probably taken from a different BIOS version. Mine has both a PWN and a DC circle that i can select, switching between them has no effect, fan still runs at 2500 rpm. Clicking on the already selected circle does nothing.

In the Msi forums thread i linked above someone with my same issue got this response from an admin:

"It's turn one that those boards A320M-A PRO/A320M-A PRO M2/A320M-A PRO MAX,
do not have hardware support for DC FAN Mode.

This option will be removed with next beta BIOS as its not supported by hardware. "

I'm running a BIOS version from last year, Don't see the point of updating it when i haven't had any (other) issues.

2500 rpm is hella loud, so i'm gonna get either a PWM fan or a low rpm molex fan to replace it.

 

[Paperdoc]

That's an odd one! Providing an option in BIOS that does nothing, and not including that info in the manual! I suggest getting a PWM-style (4-pin) fan. That WILL give you control of its speed which most often will be slower and quieter, but still allows high speeds when your system does need extra cooling. Check out units by Noctua. They have an excellent reputation of good air flow, lower noise, and long life - they warrant them for 6 years, and most users find they last longer. Some consider their price a bit high, and some don't like their colour schemes, and they do not make any with lights in them. One note: they often include a little device you can insert into the fan connection point called a Low Noise Adapter. It really is only a small resistor that lowers the voltage supply to the fan so it can only run at lower speed to be quieter, BUT that means it can NOT ever reach its max speed when your system needs more cooling. It is useful when you connect the fan directly to a Molex power output from the PSU. But when you are plugging into a mobo header that does speed control, do NOT use it.

Of course, there are other makers of good fans, too. In choosing, look for best max air flow, lower max noise, the PWM design, and of course the size. Size is the length of one SIDE of the square frame. Fan max speed is not really important - it's air flow you want. Max current use is not important for a single fan.

 

[Lazy Dog]

Thanks for the advice, will look into it.