Re: cpufreq* help.

From	Todd <Todd@invalid.com>
Newsgroups	comp.os.linux.misc
Subject	Re: cpufreq* help.
Date	2011-04-22 21:38 -0700
Organization	A noiseless patient Spider
Message-ID	<iotl46$n3a$1@dont-email.me> (permalink)
References	<iossat$mt6$1@speranza.aioe.org> <iot1uh$srf$1@dont-email.me> <slrnir4khi.i7f.spamtrap42@one.localnet>

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On 04/22/2011 09:14 PM, Robert Riches wrote:
> The relationship you describe holds true for CMOS circuits.
> While nearly all current digital ICs are CMOS, there are other
> logic families (NMOS, PMOS, TTL, ECL, etc.) that do not
> necessarily run cooler with slower clock frequencies.

Hi Robert,

Definitely CMOS.  The current drain on others can be
asymmetrical, but the transition is still the soar
point for current consumption.  The faster you
run them, the more work (work done or energy
converted per unit of time) they perform,
the hotter they get.  The big push on smaller traces
is because the traces act as capacitors that have
to be discharged/recharged every time a circuit
switches state.  The faster you can charge/discharge
the trace capacitance, the faster you can go and the
less power you have to use.  And the less power, the
less heat.

And, you are correct, some digital circuits are asymmetrical.

Another generality.  The cooler you run electronic circuitry,
they longer it lasts.  (I have a giant Super Micro cooler
on top of my new CPU.)  I did a lot of Mean Time Between Failure
(MBTF) analysis back when I was a young fellow.

I think I am in a blabby mood.

-T

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Thread

cpufreq* help. "s. keeling" <keeling@nucleus.com> - 2011-04-22 21:35 +0000
  Re: cpufreq* help. Todd <Todd@invalid.com> - 2011-04-22 16:11 -0700
    Re: cpufreq* help. Robert Riches <spamtrap42@jacob21819.net> - 2011-04-23 04:14 +0000
      Re: cpufreq* help. Todd <Todd@invalid.com> - 2011-04-22 21:38 -0700
        Re: cpufreq* help. Robert Riches <spamtrap42@jacob21819.net> - 2011-04-23 04:47 +0000
          Re: cpufreq* help. Todd <Todd@invalid.com> - 2011-04-22 22:01 -0700
            Re: cpufreq* help. Todd <Todd@invalid.com> - 2011-04-22 22:04 -0700
              Re: cpufreq* help. Michael Black <et472@ncf.ca> - 2011-04-23 11:37 -0400
                Re: cpufreq* help. Bill Marcum <bill@lat.localnet> - 2011-04-23 13:22 -0400
  Re: cpufreq* help. Baron <baron@linuxmaniac.net> - 2011-04-23 20:10 +0100

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