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What is "PWM"?

post #1 of 3
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I understand how Pulse Width Modulation works. That is how a light dimmer works.

What is the deal with PWM controlled fans? Are they supposed to be better or what? What is the appeal?
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Mercury
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post #2 of 3
Quote:
Originally Posted by JDługosz View Post
I understand how Pulse Width Modulation works. That is how a light dimmer works.

What is the deal with PWM controlled fans? Are they supposed to be better or what? What is the appeal?
Typically, a fan which is designed to be PWM will spin more reliably, and quieter than a fan running on a lower voltage than designed. Additionally, there will be no losses due to running with a resistive fan controller.
    
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post #3 of 3
There are some bad PWM fans, and some fans that handle lower voltages quite well, but yeah, PWM is more efficient.
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