# Frequency scaling can damage hardware?

## Doorbreath

I've always ran everything at full speed with no power saving, lately I was considering enabling the ondemand govenor as from what I've been led to believe I shouldn't notice a performance decrease? (x64_64 desktop) However I'm worried that constantly changing the frequency can't be any good for my CPU, am I just being silly?

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## NeddySeagoon

Doorbreath,

Modern CPUs are designed to support this sort of thing.

Older CPUs back as far as the k6-2, at least has a low power halt state, which is still provided today.

In short, it won't make much difference to the extreames of thermal cycling the CPU undergoes but it will spend less time at the thermal peak as it will still do useful work at the lower clock speeds allowed by changing the CPU core clock.

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## Doorbreath

Thanks Neddy, I'll try it out, will be interesting to see what the idle temp is (that's if I'm reading understanding the sensors output properly, which I guess is another thread lol).  Out of curiosity, does windows do any kind of frequency scaling, by default?

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## NeddySeagoon

Doorbreath,

The idle temperature should change very little as the CPU will still be halted when there is nothing to do.

If the CPU did not reach thermal equilebium when it was idle before, you may see a small drop in the idle temp.

This has nothing to do with the way the CPU idles, its just not getting as hot when its working.

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## Doorbreath

OK thankyou for explaining, maybe you could help with my sensors output,

 *Quote:*   

> f71858fg-isa-0a00
> 
> Adapter: ISA adapter
> 
> in0:         +1.67 V
> ...

 

Which is the one I should focus on? Or all 3?  I don't understand the 15.5C one...

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## NeddySeagoon

Doorbreath,

Look in the sensors  /etc/sensors.conf file and on the lm-sensors website.

Many motherboards are made with different sorts of sensors. The two types are diode and thermister.

They have wildly different characteristics and you have to edit sensors.conf to suit your particular sample of the motherboard.

You may well find comments in sensors.conf for various configurations of your motherboard, its likley to be on lm-sensors website too, along with some more generic help.

You can tell when its right as the numbers will be close to those reported in the BIOS.

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## kolcon

 *Doorbreath wrote:*   

> However I'm worried that constantly changing the frequency can't be any good for my CPU, am I just being silly?

 

I think that if HW can be destroyed by SW, it fully deserves it  :Wink: 

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