Question on fan speeds, PWM and such.

Firedrops

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Apr 22, 2012
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Hey guys I'm a little confused about the ways and ease of regulating case fan speeds.
As of now all the fans I'm considering are either 3-pin or 4-pin PWM.

My other relevant specs would be:
NZXT Phantom 410
i5-3570k
Gigabyte's GA-Z77X-UD5H-WB

With this set up, how hard is it to configure 3-pin(or non-PWM) fans to ramp up or down(I assume the factor to be changed here is the fan's RPM) in accordance to component temperatures, as compared PWM fans? Is it possible at all?

I know the case itself has a hardware 3-stage fan speed controller, but I would like to have the process automated, if possible.

Thanks in advance for your patience and answers!
 
Solution
Gigabyte's motherboards have terrible fan control options. If you don't have that board yet, consider an Asus.

Other than that, a 3pin fan is adjusted based on Voltage to the fan. Usually between 7-12Volts determines the fan speed.

PWM is controlled by pulsing the motor on and off very rapidly to spin the fan.

3 pin can be controlled by a motherboard, as well as PWM, but most PWM fans don't behave well on fan controllers, as they are usually just adjustable resistors that change the voltage to the fan.

A nice fan controller like the NZXT Sentry LXE would bridge the gap and allow you to manually set the automatic control. Plus it looks cool.

http://www.nzxt.com/new/products/fan_control/sentry_lxe

ngrego

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Jan 25, 2012
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I have never used software to control fan speed so I can't say much about how or if it works well. What I can say though is that it would probably be best to get 4pin PWM fans if you haven't made your purchase yet. 4pin PWM fans can be controlled directly by your mobo and provide the appropriate speed and cooling for your system automatically. Thay can also be manually set as you see fit.
Another option is to use a fan controller that can connect to one header on the mobo and controll many fans either manually or via the PWM header on the mobo.
A well planned fan setup and a tidy case will also help keep temperatures at a desired level and not disrupt the airflow inside the case.
 

dannoddd

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Apr 14, 2010
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Gigabyte's motherboards have terrible fan control options. If you don't have that board yet, consider an Asus.

Other than that, a 3pin fan is adjusted based on Voltage to the fan. Usually between 7-12Volts determines the fan speed.

PWM is controlled by pulsing the motor on and off very rapidly to spin the fan.

3 pin can be controlled by a motherboard, as well as PWM, but most PWM fans don't behave well on fan controllers, as they are usually just adjustable resistors that change the voltage to the fan.

A nice fan controller like the NZXT Sentry LXE would bridge the gap and allow you to manually set the automatic control. Plus it looks cool.

http://www.nzxt.com/new/products/fan_control/sentry_lxe
 
Solution

Firedrops

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Apr 22, 2012
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Thanks for the simple but concise explanation, dannoddd.

Didn't choose Asus because of the (relatively)bad sound card except from Deluxe onwards, which was far out of my budget. Might go with MSI's GD65 instead, though.

I can't afford any decent fan controllers, my initial budget already stretched quite a bit.

Alternatively, can you recommend any fans that are comparable the Gentle Typhoon AP15, but is PWM?