A Rant About PWM (in general) & Z97 MBs

its going to boil down to

different fans
different cases
different controllers
different ears

different opinions

diplomat hat firmly on!
 
At RPMs that actually do something >500-600, I have not heard ticking. If it happens at 300RPM, it is a different thing. If the motor has some sort of noise it is not due to the PWM. My F14s make noise from the motor at any RPM and my Fractal 14cm fans make noise as well, first are PWM controlled, second are 3 pin voltage controlled. This is just bad bearing that is too quiet to be heard when the fan is at full speed. It has nothing to do with the PWM.
 
solutions:
wear headphones
move computer out of the room so you cant hear it at all [also keeps room cooler]
ignore the tick/be less sensitive to noise
passive cooling
listen to loud heavy music until you partially lose hearing
get a different hobby

never heard a tick from any of my pwm fans [all corsair units], either i cant hear it or it aint there.
 
I have a couple of PWM fans, no ticking here. Mine run great - my headers are all true PWM as well :o
 
Assume that was you slowing them down when not needed, were they ok at 100% speed?


No mate i do not control them the 120mm's run full speed inside my Z77 build from the Asus 4 pin PWM motherboard slot of which i disable al controls in bios. Only the 140mm hoover on the side was controlled as it is flippin awful. But if you have the case anywhere but under the desk the buzz click will drive me insane as my ears can hear it. Akasa apache are just awful there is a thread here about the ticking.


I cannot remember if i started it but i know i had a complaint to OCUK about Apache "Ultra Silent" claims. I now have that whole build for sale and have the rig in my sig with Corsair. I really need to fire it up and test for clicking but i will bet i can hear it from them too.
 
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You can't base the overall tick no tick down to one reference, that's just the guy from Noctua's opinion. I have always used PWM and have never heard any ticking, ever. I use the Akasa Viper 120 / 140, and as far as I'm aware they are the same as the Apache's apart from the colour, and no tick, I've tried them at full / 75 / 50 / 25, and a mixture of in between and lower, and to me and 6 other people I have had listen to them still no tick.
 
I already did in post #9.

QUOTE:


Noctua Announces New PWM Fans

Press Release by
btarunr
Wednesday, November 30th 2011 12:21 Discuss (21 Comments)
Enlarging its portfolio of premium quality quiet fans, Noctua today announced PWM versions of its renowned NF-P12, NF-B9 and NF-R8 fans. Having received more than hundred awards and recommendations from the international press, the classic NF-P12, NF-B9 and NF-R8 fans helped to found Noctua's reputation as a top-tier manufacturer of premium grade quiet cooling components. The new PWM versions build on the proven designs and feature Noctua's novel NE-FD1 IC for fully automatic control and ultra-low power consumption.

"Our customers have been asking us for PWM versions of our fans for a long time, but the available PWM fan driver ICs simply weren't up to our quality standards", explains Mag. Roland Mossig, Noctua CEO. "With our NE-FD1, we've now got our custom-designed IC that allows us to build PWM fans that consume less power and remain quieter at low speeds."


Most conventional PWM fan driver ICs put out square signals that cause sudden torque impulses. These impulses can cause minute deformations of the entire fan structure which lead to audible "clicking" noises that are especially noticeable with many common PWM fans running at slower speeds. Adopting Noctua's Smooth Commutation Drive (SCD) technology, the custom designed NE-FD1 PWM IC slows down the slew rate of the output signal in order to give a smoother, less sudden torque impulse. This way, PWM switching noises can be effectively suppressed and the fan runs even quieter, especially at low speeds.

Noctua's NE-FD1 IC was not only fine-tuned for superior quietness, it has also been carefully optimised to allow for ultra-low power consumption. As a result, the new PWM models consume 25-40% less power than their non-PWM counterparts.

All models come with Low-Noise Adaptors, 30cm cable extensions and 4-pin y-cables that allow to connect a second PWM fan to the same fan header for automatic control. Equipped with Noctua's signature SSO bearing and topped off with a 6 years manufacturer's warranty, the NF-P12 PWM, NF-B9 PWM and NF-R8 PWM are a proven premium choice for the highest demands.


http://www.techpowerup.com/155944/noctua-announces-new-pwm-fans.html

You might be right, they might be on to something but that sounds like a hair conditioning advert. "Now with revitalisit, the special compound that adds... stuff... THAT NO-ONE ELSE HAS!!"
 
I have one PWM fan. It ticks at lower rpm. It also stalls when run on too low a voltage.

PWM control is great for the fine control it gives you but really it is so much better with a bit of smoothing, like my PWM converter provides.
 
I have one PWM fan. It ticks at lower rpm. It also stalls when run on too low a voltage.

PWM control is great for the fine control it gives you but really it is so much better with a bit of smoothing, like my PWM converter provides.

PWM fans are not meant to be voltage controlled. It should always be 12V, the control is by changing the PWM signal.
 
You might be right, they might be on to something but that sounds like a hair conditioning advert. "Now with revitalisit, the special compound that adds... stuff... THAT NO-ONE ELSE HAS!!"

I agree, I do not think someone is that naiive that a small PWM controller can create a perfect square wave. It will always be with slopes so their "solution" is purely marketing. And as I said, if the speed of the motor was regulated as you suggest - by turning it on and off - they do not need a PWM signal at all, just modulate the 12V power supply and you will get ticking, vibrations and a hell of a lot other nasty effects of this nonsense. The PWM is one of the simplest and most reliable forms of signal modulation so it is a great translation of a simple percentage number from digital to analogue sent via a wire, nothing else. You might hear single ticks as the voltage goes up and down rapidly on RPM change but if the RPM is constant, there is no change - signal received is the same, voltage supplied to the motor is the same, RPM is the same, no ticking. The noise everyone describes is just bad bearing and it does not sound like ticking but more like squeaking from the friction somewhere in the bearing. As I mentioned, my fans have bad bearing too, as they are cheap Arctics, and they have a low tone squeaking noise that is present at all RPM but is heard only on low RPM. However, this does not mean they tick because they are PWM controlled.
P.S. If I am wrong and all the manufacturers are using the PWM in such a mindless way, I should start a company that makes proper PWM controll PCBs for fans... I highly doubt that every engineer in this industry but me is an absolute moron.
P.P.S. I just saw the same thread and first post into several other forums. Why? Troll?!?
 
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I have about 10 PWM fans, not a single one ticks. And my ear is very fastidious, I can clearly hear 140mm fans at 800RPM from the other end of the room. No ticking. Actually you are the first person I hear that complains about this.

You mustn't read the forums much them, PWM tick is well documented/complained about, and a 140mm @800RPM will be moving the same air as a 120mm @1000-1200RPM so of course you can hear that across a room that doesn't make your hearing good just not deaf.

I have used various Corsair SP, Akasa, Noiseblocker, etc PWM fans and every one ticked. It was extremely evident when the other fans were running at low speed (800RPM slipstreams at 500RPM via voltage control so no PWM tick).
 
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It was extremely evident when the other fans were running at low speed (800RPM slipstreams at 500RPM via voltage control so no PWM tick).
As I said, even if there are ticks, fans do barely anything both from airflow and static pressure aspect at 500RPM so I see no reason using my fans at those speeds. I use mine at about 650-700RPM at idle and I neither hear them nor the ticking. Give me some footage material with this ticking as the ones I've found are not ticking as I would describe the sound from spinning up fast a DC motor.
 
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