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MSI Motherboard and 3-pin Fan Control

Last response: in Motherboards
December 27, 2013 7:31:15 PM

My old motherboard died, so I went and bought an MSI B85M-G43 motherboard and an Intel Core i5-4570 processor.

So far, everything works very well, except my system fan. Its a 90mm stock fan (I upgraded from a Dell Inspiron 560, I kept the case and fan), and I can't seem to control its speed in the BIOS.

It runs at about 2300RPM, and for some reason it seems to be slightly loud and annoying. My CPU's temperature stays around 35-40C, and my system temperature stays at about 25-30C, both when idle.

I realize that 3-pin fans don't have BIOS or software RPM speed support, but from what I've read online, 3-pin fan speeds can be controlled by limiting the voltage applied to the fan's power.

I don't want to buy a voltage regulator (I'm cheap). I saw something having to do with controlling fan speeds and voltages, but I can't find a way to change the voltage. EDIT: Well, I closely checked the BIOS options and tinkered around with the settings, and the "Manual Fan Speed" option doesn't work. [Look here:]

TL;DR: How do I control 3-pin fan RPM speeds without the use of a voltage regular?
So if my motherboard can't control voltages to fans, does that mean my only option is to buy a voltage regulator in order to control 3-pin fan speeds?

EDIT: Well, I just remembered that I still have my old CPU lying around. I'll use that CPU's fan! yaaay :) 
a c 402 V Motherboard
December 27, 2013 8:58:50 PM

Check on page 3-28 of your MB's manual. It explains the CPU and SYS FAN speed control. It appears to be a manual setting only for the SYS fans. In the older MBs they used to have something called Smart Fan that worked with both the CPU fan and the SYS fans. That seems to be athing of the past now.