add arrow-down arrow-left arrow-right arrow-up authorcheckmark clipboard combo comment delete discord dots drag-handle dropdown-arrow errorfacebook history inbox instagram issuelink lock markup-bbcode markup-html markup-pcpp markup-cyclingbuilder markup-plain-text markup-reddit menu pin radio-button save search settings share star-empty star-full star-half switch successtag twitch twitter user warningwattage weight youtube

Is PWM overrated?

PrivatePengu

1 month ago

HardwareCanucks made a video where they said that PWM enables...

  • Full precise control of RPM [speed] range

  • Set RPM [speed] to reflect on hardware temperatures

  • Really low RPM for really silent, almost inaudible, operations

My isssue here is that I have 3-pin fans and I don't think the difference in control is really all that visible. I mean, I can set 0-RPM on my fans aswell and set fan curves based on hardware temperatures - just not as precisely. As long as your motherboard is capable of this and has the right software, is the difference really good? What about the price?

Discuss = )

Comments

  • 1 month ago
  • 1 point

Well some of us are more noise sensitive than others or the PC is being used in an application where they can't make a lot of noise. Couple examples, using one as a home theater PC (HTPC) or PC stays on but is in the same room you sleep in. Now when you need to push your hardware they can speed up and generate the performance needed for the cooling. Thus only making noise when it absolutely has to.

Now some motherboards can use DC can control on 3 pin fans but not all are able to do that. Now I am not sure what fans you are using but many 3 pin fans only run at certain speeds to keep noise down. Let me use a couple of Noctua fans as an example:

Noctua NF-P12 redux-1300 54.32 CFM 120 mm Fan. Only 19.8 db in noise so a rather quiet fan. It is a 3 pin fan so normally it will run at 100% speed the entire time.

Noctua NF-F12 industrialPPC-2000 PWM 71.69 CFM 120 mm Fan. At max speed they will be louder at 29.7 db which still isn't too bad noise wise and it has much more airflow and pressure (3.94 mmH₂O vs 1.68 mmH₂O) because its 100% speed is much faster than the other fan. As this is PWM you can slow this fan down to match the other fan for when cooling isn't needed as much so you can lower the noise.

Sure you can buy 3 pin fans that are as loud or louder than either of those fans that can push more airflow. You can use a fan like this for some mega airflow but also at 44 db in noise it will sound like a jet engine next to you.

Some people just don't care about fan noise but others do. It is not wrong to use 3 pin fans at max speed all the time and as long as you are happy with your PC isn't that what matters most?

  • 1 month ago
  • 1 point

Yes, they are more efficient too. My asus will run DC fans as well but it has to feed them maybe 75% power to get them to run maybe 60% speed (whatever it is) for a low speed, so you can't slow them down as much and they are less efficient at lower speed. They wont start below that point. These are low speed quiet case fans so no big deal, but not as capable. I mean some people just hook them to the PSU and leave them full speed all the time and its fine, with a 1500 rpm fan its not bad, but you have no adjustment either. I don't want to hear them, power them, or fill my case with dust unless I need to...so a couple bucks more would be worth it to me for pwm.

Sort

add arrow-down arrow-left arrow-right arrow-up authorcheckmark clipboard combo comment delete discord dots drag-handle dropdown-arrow errorfacebook history inbox instagram issuelink lock markup-bbcode markup-html markup-pcpp markup-cyclingbuilder markup-plain-text markup-reddit menu pin radio-button save search settings share star-empty star-full star-half switch successtag twitch twitter user warningwattage weight youtube