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Will a 3-pin header control the Fan Speed?

Hi!

My mobo is a Gigabyte G41M- Combo with,
* 1 x 4-pin CPU fan header
* 1 x 3-pin SYS fan header

But I want at all 4 x case fans to be connected. & I thought of using a fan splitter for that single 3-pin header.

So, will the 3-pin header automatically regulate the fan speeds according to the system temperature?
& since I connect 3 x fans (parallel) simultaneously, will there be any problem in regulation?

And I know that I can do this by directly connecting to the Power Supply.
But I'm concerned about the noise that these 3 fans are going to make at full throttle.

Even though, can I directly connect those? Won't there be any there any voltage issues?
[PSU - PowerLogic Magnum Pro 275 (550W) with 3 x Molex (4-pin)]
5 answers Last reply Best Answer
More about will header control speed
  1. Best answer
    I would reccomend against connecting three fans together on a single Motherboard header because you might draw enough current to burn out that connector which could damage your Mobo. Putting two fans on a single header is usually OK.

    Generally, you won't get any control over the fan speed using a three pin header. PWM fans require 4 pins in order to control the fan speed. The best way to control fans speeds using three pin headers is to get a fan controller.
  2. Looking at the manual for that motherboard, it appears it does not support automatic can speed control from the sys_fan header.

    If you're worried about noise, one trick people do, is rewire the fan connector so that when you connect it to the power supply, you ground to the +5V instead of ground, operating your fan at 7V instead of 12V. That, or there are plenty of fan speed controllers you can get, such as a simple inline resistor, all the way to temperature controlled systems.
  3. Best answer selected by Trailbreaker.
  4. JKatwyopc said:
    I would reccomend against connecting three fans together on a single Motherboard header because you might draw enough current to burn out that connector which could damage your Mobo. Putting two fans on a single header is usually OK.

    Generally, you won't get any control over the fan speed using a three pin header. PWM fans require 4 pins in order to control the fan speed. The best way to control fans speeds using three pin headers is to get a fan controller.


    Thanks man! U saved a Motherboard! :wahoo:
  5. zyky said:
    Looking at the manual for that motherboard, it appears it does not support automatic can speed control from the sys_fan header.

    If you're worried about noise, one trick people do, is rewire the fan connector so that when you connect it to the power supply, you ground to the +5V instead of ground, operating your fan at 7V instead of 12V. That, or there are plenty of fan speed controllers you can get, such as a simple inline resistor, all the way to temperature controlled systems.


    Thanks! But, do you think that can save a big noise from 3x 140mm fans?
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