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My power options include an active or passive CPU setting. Which do I want?


I recently noticed a setting in my HP Slimline Desktop running Windows 7
Home Premium, Service Pack 1, which I’m not sure about. In Control Panel under
Power Options, Advanced Settings, Process or Power Management, the system
cooling policy, I have an option of a passive setting. It slows down the
processor before speeding up the fan. Or an active setting that slows down the
processor after speeding up the fan. By default, it was set to passive, but it
makes more sense to me setting it to active. I’m not a hard gamer or anything
except maybe for chess. I just normally watch it or burn DVDs. I looked for a
related topic by can’t find anything. What do you think my setting should

In this excerpt from
Answercast #58
, I look at heat settings and how they determine when your
fans will kick in to cool your computer.

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Power management settings

To be honest, I don’t know. The setting is actually fairly clear.

What’s happening here is that when your processor works hard, it gets hot.
And when it gets hot, it needs to be cooled down. Cooling it down is usually
done by a fan that blows air across what is probably a large metal heat sink
that’s attached to the CPU.

Now, you have a choice to make.

Slow the machine

You can instruct the computer to slow down; to not work as hard if it’s
starting to heat up – so that the processor doesn’t get as hot – so that the
fan doesn’t need to turn on as quickly or perhaps run as fast.

The downside of that? Well, the processor is going to run a little slower.
It’s going to run a little slower than perhaps it could. But in doing so, it’s
going to keep itself a little cooler.

Run the fans

Now, the other side of that coin is keep the processor running faster; fire
up the fan first. In other words, don’t slow down the processor until you’ve
done everything else possible.

The downside here of course is that you’re going to hear your fan come on
more often. The fan is going to be blowing air across the processor more often
as the processor works hard.

If the processor is not working hard (in other words, if it’s idling if
you’re playing chess), the computer I swear is spending most of its time doing
nothing. If you’re surfing the internet, if you’re reading email, the processor
is spending most of its time doing nothing.

In either case then, it doesn’t really matter what the setting is. The
setting only really kicks in if you ask your computer to do something that is
considered to be computationally intense, which means the CPU itself really has
to work hard at crunching numbers and performing calculations. That’s when the
CPU heats up.

Light computer use

If you never heat the CPU up, it honestly doesn’t really matter what the
setting is.

I would be tempted myself to leave it in the active position simply because if I’m doing something that is processor intensive, I probably am doing it for a reason and I probably don’t want it to slow down unless absolutely necessary. I will pay the price, so to speak of having the fan turn on, of having to listen to the fan turn on.

And that may not be a price for you at all. Many fans run pretty quietly. In
my particular case, my machine has a fairly noisy fan when it comes on at full
speed. But in your case, it may not.

Like I say, that’s why it’s a decision that is really, really up to you.

Heat vs. noise

So, those are my suggestions. I don’t know. Like I said, it depends so much
on how you use your computer and what your own personal preference is for
things like heat vs. noise.

My guess is, if you’re not pushing your computer very hard, the bottom line
is it may not make one whit of difference what you set this to.

Do this

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