Connecting 4-pin Molex Fans to the motherboard.


Caliper Novice
Original poster
Feb 15, 2017
Hello everyone!

This might be a stupid noobish question but I've never done anything like that before so please help me.

So my graphics card fans are very loud for my taste even at the lowest speed to I thought I can remove the shroud and fans and put 80mm fans next to it. I had two fans that are connected to a single 4-pin Molex connector.

Each of them has a red and black cable so what I did is I cut a cable from a non working 120mm fan, connected two red cables and two black cables from the fans to each other and then connected these to the cable with 3-pin connection that goes into the motherboard header. I also extracted the pin of yellow cable from the 3-pin connector to remove it using a toothpick.

I plugged this mess into the motherboard and it seems to be working and both fans are spinning but I just wanted to make sure that this solution is safe and will work in the long term.

Also I need to know if I can connect these fans to a single small 2-pin connector which goes to the grapchics card fan header to control their speed.

Thanks in advance for any suggestions.


Airflow Optimizer
Feb 26, 2017
Which GPU do you have? Most have 3 pin pwm fans, just with a mini version of the header. I was able to find a mini to full size pwm cable on amazon for something like $6. Super simply plug and play, and now I have a quiet Noctua fan cooling my GPU. There are also PWM splitter cables to turn one channel into two.