What Is a DC Fan?
Because of this, this pin is also frequently known as the tachometer pin.
This lets your PCmonitor fan speedsand alert you if a fan stops spinning.
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DC fans can either run at a constant speed or change speeds as controlled by the motherboard.
For a lower speed, the motherboard sends less voltage into the fan.
DC fans are the more “traditional” bang out of computer fan.
The Noctua NF-S12B redux-1200 PWM fan combines effective cooling with quiet operation, making for a workhorse fan you can rely on.
What Is a PWM Fan?
DC fans use varying current to control fan speeds.
PWM fans, on the other hand, only use a constant voltage, usually 12V.
DC fans use three-pin connectors, while PWM fans use four-pin connectors.
When a computer doesn’t need much cooling, slowing the fans lets it keep noise levels lower.
In general,PWM fans are quieterthan DC fans.
Because they can more easily spin down, PWM fans generally wear less over time.
There is one other area where the varying voltage of DC fans is an issue: noise.
DC fans operating at less than their normal voltage of 12V will create electrical noise.
If you’re using your PC foraudio production, this noise can be a major problem.
Which Is Better?
Despite the clear advantages of PWM fans, you’ll still find DC fans includedin most pre-built PCs.
Evencaseswith included fans typically use DC fans rather than PWM.
This is mainly for cost reasons, as DC fans are cheaper.
That said, DC fans aren’t just the more affordable option.
If you want more control over your PC, PWM is generally the way to go.
PWM fans also win when it comes to a quiet PC build.
Check your motherboard’s headers to double-check you’re buying the right fan for your PC.
