3-pin fan control on 4-pin header in budget boards

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   Hello!
I am interested in the B250M-HDV as mainboard for my new system.
The system is supposed become as quiet as possible with reasonable monetary effort.

I will equip an Intel G4560 CPU with a powerful heat sink with the intent to disable the CPU fan in light use of the PC.
My plan is to have a high quality 120 mm fan running at very low RPM in the rear of the case to provide the needed ventilation.

Moving on to my questions:
Most 4-pin PWM fans are noisier than 3-pin voltage controlled fans due to problems with commutation of the 12 V PWM signal, resulting in the fan bearings showing clattering sounds which become very noticeable at low speeds of the fan due to the reduced air flow.
To avoid those noises, my case fan of choice is 3-pin voltage controlled.
Obviously I don't want the fan to operate at maximum speed at a voltage of 12 V just like uncontrolled 3-pin fans plugged into a 4-pin header do, but instead at approximately 30 % of the maximum speed.
I searched the forums and found the following topic which is related to mine but covers relatively more expensive mainboards than the budget one I have in mind:
http://forum.asrock.com/forum_posts.asp%3FTID=2270&PN=1&title=asrock-bios-fan-control-is-it-equal-on-all-models

Since the specifications of B250M-HDV don't mention that its 4-pin headers offer Smart Fan Speed Control like the mainboard in the aforementioned thread, I would like to clear up some open questions before purchasing a mainboard that potentially does not offer what I need.

For 4-pin headers without Smart Fan Speed Control, can I manually select whether the connected fan is being controlled by voltage or PWM?
If that is not the case, is it at all possible to control a 3-pin fan plugged into one of the mainboards 4-pin headers or will it run at max speed/12 V no matter what?
If control is possible, when setting up 5 CPU temperatures and assigning fan speeds to them, will I be able to assign them across the entire range of 0-100 % or is there a minimum threshold?
Many thanks in advance

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LouisXIV Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 25 Feb 2017 Status: Offline Points: 3	Post Options Post Reply Quote LouisXIV Report Post Thanks(0) Quote Reply Topic: 3-pin fan control on 4-pin header in budget boards Posted: 25 Feb 2017 at 8:39am
	Hello! I am interested in the B250M-HDV as mainboard for my new system. The system is supposed become as quiet as possible with reasonable monetary effort. I will equip an Intel G4560 CPU with a powerful heat sink with the intent to disable the CPU fan in light use of the PC. My plan is to have a high quality 120 mm fan running at very low RPM in the rear of the case to provide the needed ventilation. Moving on to my questions: Most 4-pin PWM fans are noisier than 3-pin voltage controlled fans due to problems with commutation of the 12 V PWM signal, resulting in the fan bearings showing clattering sounds which become very noticeable at low speeds of the fan due to the reduced air flow. To avoid those noises, my case fan of choice is 3-pin voltage controlled. Obviously I don't want the fan to operate at maximum speed at a voltage of 12 V just like uncontrolled 3-pin fans plugged into a 4-pin header do, but instead at approximately 30 % of the maximum speed. I searched the forums and found the following topic which is related to mine but covers relatively more expensive mainboards than the budget one I have in mind: http://forum.asrock.com/forum_posts.asp%3FTID=2270&PN=1&title=asrock-bios-fan-control-is-it-equal-on-all-models Since the specifications of B250M-HDV don't mention that its 4-pin headers offer Smart Fan Speed Control like the mainboard in the aforementioned thread, I would like to clear up some open questions before purchasing a mainboard that potentially does not offer what I need. For 4-pin headers without Smart Fan Speed Control, can I manually select whether the connected fan is being controlled by voltage or PWM? If that is not the case, is it at all possible to control a 3-pin fan plugged into one of the mainboards 4-pin headers or will it run at max speed/12 V no matter what? If control is possible, when setting up 5 CPU temperatures and assigning fan speeds to them, will I be able to assign them across the entire range of 0-100 % or is there a minimum threshold? Many thanks in advance