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by duped 843 days ago
I would be surprised that a PID controller can't adjust the control signal of the fan on the order of milliseconds/hundreds of microseconds. The mass of the fan would be the bigger issue.

Something that would help is multiple fans being adjusted by the same PID controller. It's not a problem if they're spinning too fast, but if you need more cooling the controller needs to increase air flow at the fastest rate which means turning up multiple fans.
2 comments
lostlogin 843 days ago
Fans are annoying enough when at a steady speed, but a fan that is continually changing speed sounds extra irritating if it’s in the same room.

Some sort of smoothing plus a conservative base rate might be more tolerable.

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guappa 843 days ago
> a conservative base rate

Do you use windows?

I find that with windows the fan is always spinning, even if at low speed. While with linux most of the times it is not spinning at all.

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fennecbutt 842 days ago
>Do you use windows

In a desktop the motherboard controls the fans unless you have an alternative like fan control installed, so not windows.

In a laptop it's either still the motherboard, or a specific chip used to manage the fans and other peripherals (ie for Dell/XPS it's locked out of bios control and you need to use Dell's special software to adjust it; Fuck You, Dell!), so still not Windows.

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guappa 842 days ago
Well a basic windows install will keep the CPU more occupied than a basic linux install, when both are idle.

This reflects in the CPU being hotter, which reflects in the fan spinning more.

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whywhywhywhy 843 days ago
In windows my CPU fan is always spinning although silently in my experience but my case fans spin down.

ASUS motherboard Noctua fans if that makes a difference.

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lostlogin 843 days ago
I’m on a Mac - and for the first time a computer I can’t hear (it’s a model with a fan).
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guappa 843 days ago
Mac tend to run hot to be more silent.

I had to throttle my CPU in my macbook or it would shutdown for overheating while compiling.

I don't consider that a feature.

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jamespo 843 days ago
sounds like an intel mac
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crote 843 days ago
The problem is that you really don't want the fans to react that quickly. Fans make noise, and a changing noise is far more irritating than a constant buzz in the background.

You quickly stop hearing a fan constantly running at 50%, but a fan randomly switching between 10% and 100% gets on your nerves extremely quickly.

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