PWM Fans (PWM Functionality) Do Not Work

[Anonymous00001]

Hi, my PWM fans in my build aren't working. Here's my fan setup:

 

I have a 8-port fan hub that supports PWM. One port is 4-pin and the other seven are 3-pin. The fan hub is connected to my motherboard's CPU cooler header using a 4-pin connector. My CPU cooler is connected to the one 4-pin header on the fan hub. All other fans are connected to the 3-pin headers.

 

I cannot control fan speed for some reason. Stuck at ~1450RPM unless I overclock my processor in which they automatically increase, but I can't manually change it.

[W-L]

4 minutes ago, Anonymous00001 said:

Hi, my PWM fans in my build aren't working. Here's my fan setup:

 

I have a 8-port fan hub that supports PWM. One port is 4-pin and the other seven are 3-pin. The fan hub is connected to my motherboard's CPU cooler header using a 4-pin connector. My CPU cooler is connected to the one 4-pin header on the fan hub. All other fans are connected to the 3-pin headers.

 

I cannot control fan speed for some reason. Stuck at ~1450RPM unless I overclock my processor in which they automatically increase, but I can't manually change it.

Is this a unit built into a case like this from NZXT, if so they are 3 pin and not capable of PWM. Those hubs are designed to take in a PWM control signal and provide an equivalent 3 pin DC voltage control signal to the fans. 

 

[Anonymous00001]

1 hour ago, W-L said:

Is this a unit built into a case like this from NZXT, if so they are 3 pin and not capable of PWM. Those hubs are designed to take in a PWM control signal and provide an equivalent 3 pin DC voltage control signal to the fans. 

 

It doesn't support PWM functionality? I thought that it would except if you change one it changes all...

[W-L]

4 minutes ago, Anonymous00001 said:

It doesn't support PWM functionality? I thought that it would except if you change one it changes all...

If it's that version in the pic, it's more complicated actually since it has to take a PWM input and provide an equivalent DC voltage control signal but all the headers are controlled. What fans are you using all 4 pin fan??

 

[Anonymous00001]

9 hours ago, W-L said:

If it's that version in the pic, it's more complicated actually since it has to take a PWM input and provide an equivalent DC voltage control signal but all the headers are controlled. What fans are you using all 4 pin fan??

 

All of the fans I'm using are 4-pin PWM fans. Corsair ML120 and ML140s.

[W-L]

5 hours ago, Anonymous00001 said:

All of the fans I'm using are 4-pin PWM fans. Corsair ML120 and ML140s.

They should still be speed controlled but instead of using PWM, they will be DC voltage controlled. If you would like everything to be on PWM you will need a 4 pin splitter like this here that is powered. 

http://www.swiftech.com/8-WayPWMsplitter-sata.aspx

[Anonymous00001]

2 hours ago, W-L said:

They should still be speed controlled but instead of using PWM, they will be DC voltage controlled. If you would like everything to be on PWM you will need a 4 pin splitter like this here that is powered. 

http://www.swiftech.com/8-WayPWMsplitter-sata.aspx

Ah ok. I think that explains why my fans' speed increase when I overclock my processor?

[W-L]

4 minutes ago, Anonymous00001 said:

Ah ok. I think that explains why my fans' speed increase when I overclock my processor?

Yes that would be why if the PWM input is on the CPU header as that will increases everything on the hub as the CPU changes with load. 

[Anonymous00001]

2 hours ago, W-L said:

Yes that would be why if the PWM input is on the CPU header as that will increases everything on the hub as the CPU changes with load. 

Thanks!