Noctua NF-S12A FLX, ULN and PWM

[Sena]

I was planning to buy a Noctua fan as an exhaust fan but there is three different kinds, FLX, ULN, and PWM which obviously means they each have different purposes but which one should I get as an exhaust fan?

[helping]

FLX is able to operate at three different RPM variations, ULN includes low noise adapters and is intended for silence (voltage/RPM reductions) normally operates at lower RPM than FLX, PWM is 4pin PWM speed controlled.

 

you'll probably want FLX. It still comes with a low noise adapter and you can control by voltage anyway.

[Sena]

FLX is able to operate at three different RPM variations, ULN includes low noise adapters and is intended for silence (voltage/RPM reductions) normally operates at lower RPM than FLX, PWM is 4pin PWM speed controlled.

 

you'll probably want FLX. It still comes with a low noise adapter and you can control by voltage anyway.

You're always helping me hahaha, thanks again for helping!

[MrSuperb]

I was planning to buy a Noctua fan as an exhaust fan but there is three different kinds, FLX, ULN, and PWM which obviously means they each have different purposes but which one should I get as an exhaust fan?

 

If your motherboard can control fans via PWM you obviously would want the PWM version !

[MrSuperb]

FLX is able to operate at three different RPM variations, ULN includes low noise adapters and is intended for silence (voltage/RPM reductions) normally operates at lower RPM than FLX, PWM is 4pin PWM speed controlled.

 

you'll probably want FLX. It still comes with a low noise adapter and you can control by voltage anyway.

 

FLX can be operate at pretty much any speed between a maximum of 1200 rpm and probably about 300 rpm. It comes with two resistors to control the maximum fan speed.

 

She probably wants the PWM version, as it can both be voltage and PWM controlled and slowed down to 300 rpm as well.

[Sena]

FLX can be operate at pretty much any speed between a maximum of 1200 rpm and probably about 300 rpm. It comes with two resistors to control the maximum fan speed.

 

He probably wants the PWM version, as it can both be voltage and PWM controlled and slowed down to 300 rpm as well.

She, I am a she. Thanks for the info, I'll have to do some thinking to see which one I should get.  She

[helping]

FLX can be operate at pretty much any speed between a maximum of 1200 rpm and probably about 300 rpm. It comes with two resistors to control the maximum fan speed.

 

She probably wants the PWM version, as it can both be voltage and PWM controlled and slowed down to 300 rpm as well.

In my experience if you want to do voltage control then the 3 pin fan is preferred.

 

From what I've seen from Noctua, I have a few NFF12's, they do not respond at all to 5v, some turn on and some fail to start at 7v. This was under voltage control, which was not how they were intended to be used since they were PWM. Some PWM fans can be controlled by voltage fine, but from what I've seen I wouldn't expect Noctuas to.

 

Most fan controllers use 3 pin (especially integrated), CPU fans used 4 pin, 3 pin should be preferred unless you want to tie exhaust fan to CPU fan.

 

@Sena you'll need to decide how you want to control it before you buy one.

 

Like I said, the ULN is simply the slower (therefore quieter) version. Most people buy FLX and use LNA/ULNA with voltage control.