[SOLVED] Standard or PWM fans in a gaming pc?

[stiffmeinster]

Which is better?

 

[RememberThe5th]

PWM if you wanna to control them with your choice of rpm/loudness of them.
Unless your motherboard offers DC control with 3pin heads.

 

[Karadjgne]

Pwm is better, but for only 3 reasons.
First is they run slower. Your average DC fan has a usable range of 7v-12v, really good fans hit 5v-12v. That translates to most fans hitting 60%-100% duty cycle and good fans get as low as 40%. Ordinarily that's not bad as such, but on 2000rpm fans would mean your minimum speed at idle is still 800 or 1200rpm, so can be somewhat not silent. Good pwm fans get under 20%, so even a 2000rpm fan at idle is only 400ish rpm. Silent.
Second is gangability. A fan header has an average amperage rating of @1A. DC fans are usually rated (nowadays) at around 0.3A or more with RGB/leds. That means it's safe to only put 2 maybe 3 fans on a single header. Any more than that and you'll be spending out on a hub or fan controller. Pwm fans work on a signal wire at a constant 12v, so a simple powered splitter (power pulled from the psu directly) can easily power upto 8 fans with just the signal being split, no amperage draw on the header. This is very handy for ppl wanting 4 or 6 fan push/pull radiators and having 1 control for all the fans.
Lastly is lighting. DC fans work by moderating the 12v, from 7v-12v. So at low speeds, led lighting powered by the fan header is also getting 7v. Dim lights at slow, gets brighter with speed. Pwm fans are a constant 12v, so led brightness isn't affected.

DC fans are better for 3 reasons.
With pwm, there's a signal telling the fan on/off so the fan is always (unless 100%) in a state of trying to turn on. With cheap pwm fans, this can lead to clicking noises like someone flicking a light switch on/off. That can be annoying. DC fans are voltage controlled, set and forget and they are running constantly, no clicking.
DC fans are considerably easier to manufacture, just a motor. There's no real need for extensive pwm circuitry. As a result, DC fans come in a much broader scope, everybody has several models that are usually cheaper to buy. Pwm fans can be limited to a few models and can cost more. You can get 5 decent case fans for $30 or 2 decent pwm for $25.
Lastly, DC fans are 3pin so will work on any 3 or 4pin header except the cpu_fan which is dedicated pwm. Pwm fans are 4 pin, so only work on 4pin headers or run at full speed. So DC fans have options that pwm do not. DC fans can be used directly from a psu via molex and run at a constant 5v, 7v, 9v or 12v (low/ultra low speed inline adapters) whereas pwm need a pwm signal from a motherboard header to set speeds.

Both have advantages and disadvantages, so there is no 'better' as such in general, it'll all come down to your particular wants/needs and circumstances as to which would be more advantageous.