120mm fan PWM mod help needed

[JunkBear]

I want to put a 120mm pwm fan on my case but i dont want to split the only 4 pins of cpu fan with it in case it cant take it and block the capacitors. So I want to keep the rpm wire and the pwm wire connected then cut the + and - wires to connect-mod them on a molex. Is it a good way? Will the pwm still onboard going to make it turn the way as original or i need to leave the + or - still connected to mobo too?

Thx

 

[newtekie1]

That will work. Keeping the RPM wire connected isn't necessary since the fan header can only read one RPM anyway, so having two RPM signals will likely confuse things. But for a fan to be PWM controlled you only need to connect the PWM wire to the fan header, where the fan gets power from doesn't matter.

For example, they make adapters to do exactly what you want that just split the PWM wire to multiple fan headers and have a molex or sata power connector to power the fans.

http://www.newegg.ca/Product/Product.aspx?Item=N82E16812311002
http://www.newegg.ca/Product/Product.aspx?Item=N82E16812311001

 

[JunkBear]

So basicaly I really need a pwm connector on motherboard to make it works. The pwm signal is it positive or negative and does it come from motherboard to fan or from fan to motherbaord?