One case fan running at constant 100%. Mobo fanspeed controller wont stop it. help.

[LaboonTheWhale]

Hey guys

 

So I installed a Noctua IPPC 2000RPM fan and I booted it up and it just runs at constant 100%. And as you can imagine, 2000RPM is not quiet. 

 

The fanspeed on the mobo doesn't stop it either. it controls my other fans except this one. 

 

I have no idea what to do right now. 

[JohnnyCorporalTech]

What about in the BIOS, it could be set to full speed there?

[LaboonTheWhale]

6 minutes ago, JohnnyCorporalTech said:

What about in the BIOS, it could be set to full speed there?

In bios it is monitoring it as 1935 RPM. but when I'm in bios its obviously not spinning at that speed as its quiet. 

 

I did a fan "tuning" that ASUS mobo's can do and it did the whole 0-100% and which is most effective. It set its standard speed to 300RPM like my other fans... when I reset, its normal and quiet but the moment it gets to the windows log in BAM 100% 

[JohnnyCorporalTech]

I doubt it would be the fan its self as you said it would run at 300RPM after you set it in the BIOS, So the only thing i can think of is maybe a thermal sensor is broken or windows isn't receiving any temperature data, so it automatically sets the speed to 100%.

[LaboonTheWhale]

1 minute ago, JohnnyCorporalTech said:

I doubt it would be the fan its self as you said it would run at 300RPM after you set it in the BIOS, So the only thing i can think of is maybe a thermal sensor is broken or windows isn't receiving any temperature data, so it automatically sets the speed to 100%.

I have an M-ITX board so I wish I had more fan headers  I'm already using 3 other fans. 

[SydneySideSteveSomewheres]

Operating Range 5V~13.2V DC

My old machine has a BIOS setting called "Smart fan control" and switching to this enables the motherboard to control the CPU fan speed, however, if I have a fan speed controller connected this is then the default controller. Do you have this setting and if so is it enabled?

 

Are you connecting a 4-pin PWM fan into a 3-pin header as this can make the fan spin at 100% and have you tried other software like SpeedFan? -click here-?

 

Also, it is possible to manipulate the delivery voltage by adding to the power wire a resistor that changes the voltage from 12 Volts to 7.5 Volts and would only cost a couple of cents (USD so that's under ten dollars AU ) if you can solder. Although some larger fans require more power than the motherboard can output through the header and require a fan speed hub to control them, for example, those with an operating Range from 5V~13.2V DC like the Silverstone FM181.