Optimal fan connectivity - PWM Hub vs Mobo

Discussion in 'PC Hardware' started by x86, Mar 1, 2018.

  1. x86

    x86 MDL Addicted

    Jul 8, 2011
  2. tonto11

    tonto11 MDL Addicted

    Jun 18, 2012
    #2 tonto11, Mar 13, 2018
    Last edited: Mar 14, 2018
    One normally thinks of a fan as a two wire device either plugged in, or not, on or off
    but that's not the case with modern computer fans

    Fans now have two wires to supply power, a third wire to provide control, and sometimes a fourth wire a sensor for actual fan speed

    PWM, pulse width modulation is a control signal generated on the motherboard to tell the fan or fans what to do, everything from off (no pulses) to full blast (max width pulses);
    this control signal is generated by firmware on a chip that receives temperature information from a number of sources
    the cpu, the gpu (sometimes) , the hdd, the memory and the ambient temperature on the motherboard as a whole
    my experience has been solely with laptops .

    If I were building a desktop computer from scratch I would have one two wire fan blowing all the time the computer was on
    and have the others all controlled by the chip on the motherboard as it sees fit

    The PWM hub merely provides a convenient place to plug multiple fans ,
    whether they be simple two wire fans running all the time , or multiple wire fans controlled by the motherboard through the hub .

    My interpretation of cpu fan is the fan mounted on the cpu heatsink to force cooling air through it. I would not mess with that.
    There should be another socket on the mobo especially for the pwm fan hub

    Finally I would monitor all the temperature sensors and fan with a program like HWInfo for a while to ensure that I was getting the performance I had expected to get.