Overheating attributed to Freebsd --sysctl variables
judmarc at fastmail.fm
Tue Nov 4 12:17:05 PST 2003
On Tue, 4 Nov 2003 14:05:02 -0500, "nw1" <network101 at covad.net> said:
> > > I'm interested in those missing sysctl variables I posted @
> > > http://188.8.131.52/freebsd/installation/sysctl_variables_missing.
> > > Using a Third party
> > > application/script to fix something that was natively working or under
> > > control, I don't
> > > think, is the way to go and causes another level of complexity.
> No problem, I am interested in any and all *sane/reasonable feedback. I
> haven't been to
> much a fan of using third party applications to fix something the
> original code or
> hardware should be able to handle.
FVCool isn't a "third party application" as I understand the term.
Perhaps a portion of the README file will make things clearer:
"As is well known AMD's Athlon/Duron is a 'hot' CPU. It really produces
a lot of heat. This is mainly because it consumes a lot of electric
power. However, there is an another reason: Generally CPU goes into
power-save mode when it is in the idle state, but in almost all the
mother boards this is prohibited in the case of Athlon/Duron mother
boards in their original BIOS settings. This software changes the PCI
configuration data of the chipset (north bridge), and allow Athlon/Duron
to go into power-save mode. The principle is very simple if you have
information. Actually, you can do exactly the same thing as this
manually by using the 'pciconf' command in FreeBSD.
"Why mother board vendors release their products with such BIOS
Well, there is a reason: There is a possibility to get the system
and/or even to hang or crash the system. Therefore, this software is
somewhat dangerous in this respect, and I will not take any
responsibilities for problems caused by using this software. Please
check the original Martin Peters's VCool web site for learning more of
So what FVCool does is utilize the 'pciconf' command to encourage AMD
CPUs to go into power-save mode when idle, a function most motherboard
manufacturers turn off for the stability reasons mentioned by FVCool's
author. As the documentation says, you can manually make these changes
with the 'pciconf' command, but why not save typing by installing the
port and running the 'fvcool' command, or run it automatically with a
Based on the names of the sysctls you're after, I'd speculate they may
operate in much (or even exactly) the same way. That is why I wondered,
in response to your advice to Paul Mather, whether those sysctl settings
would work with Intel CPUs.
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