Alexandre "Sunny" Kovalenko
gaijin.k at gmail.com
Thu May 14 00:36:35 UTC 2009
On Wed, 2009-05-13 at 17:17 -0300, Sylvio César Teixeira Amorim wrote:
> my laptop is Intel Core 2 duo 2.26, FSB 1066Mhz, DDR3.
> my sysctl
> hw.acipi.thermal.tz0._PSV: -1
> hw.acipi.thermal.tz0._CRT: 107.0C
Please, do not top-post -- it makes it harder to follow the thread.
Do you by any chance have message to the tune of
"acpi_tz0: _PSV value is absurd, ignored..."
in you boot log? "grep absurd /var/log/messages" should give you the
answer to this question.
If answer is "yes" and you are willing to override your ASL, dump it
according to the "Handbook" instructions and put it somewhere, I can get
As an alternative, you can add
to /etc/sysctl.conf. This might or might not work as BIOS might tell OS
to reevaluate _PSV and restore absurd value. You should replace 75C with
the value you have in mind for your system.
> 2009/5/13 Kevin Oberman <oberman at es.net>
> > > Date: Wed, 13 May 2009 15:33:42 -0300
> > > From: =?ISO-8859-1?Q?Sylvio_C=E9sar_Teixeira_Amorim?= <
> > scjamorim at bsd.com.br>
> > > Sender: owner-freebsd-acpi at freebsd.org
> > >
> > > I have one laptop Dell Latitude E4300 with FreeBSD-8-Current, The
> > > temperature of the processor is very high when I'm compiling the kernel,
> > I
> > > get to stay with 88 Celsius, how do I force a download this temperature?
> > Probably the first place to start is to clean the heat sink on your
> > laptop. Simply opening the unit and blowing it out with compressed air
> > can drop CPU temperature by over 10 degrees Celsius. This is probably
> > something that should be done at least annually and more often if the
> > laptop is run in dusty locations, such as sitting on a bed or table
> > covered with a table cloth.
> > It is also possible that the heatsink is not properly attached to the
> > CPU. Several people have reported that cleaning and re-applying heatsink
> > grease greatly improved the temperature.
> > Next, take a look at the values of _PSV and _CRT. (sysctl hw.acpi). If
> > PSV is higher than 88, your system is still within normal operating
> > temperatures. For example, Pentium-M chips are speced to run at a steady
> > temperature of 100C. _PSV on my laptop is 94.5C and _CRT is 99.0C. This
> > means that the system does not start doing anything beyond normal fan
> > cooling until the CPU reaches 94.5C and will reach 99C before starting
> > to shutdown. (This is different from the emergency crowbar shutdown
> > which is for thermal spikes of about 130-150C which might occur when a
> > heatsink becomes dislodged.)
> > When _PSV is reached, the system should simply slow down until the
> > temperature drops. There is hysteresis to keep it from continually
> > cycling. I don't recall numbers, though.
> > If you want to lower the temperature "manually", you can kill powerd
> > (/etc/rc.d/powerd stop) and set the CPU frequency lower. (sysctl
> > dev.cpu.?.freq) where '?' is the CPU number. The available frequencies
> > may be found in sysctl dev.cpu.0.freq_levels. If you are doing the
> > manually, be sure to adjust all CPUs to the same frequency.
> > Finally, placing the system on a surface that leaves an air gap under
> > the system will help, too. Running it on a soft surface inhibits
> > convection cooling and most soft surfaces are pretty goods thermal
> > insulators.
> > --
> > R. Kevin Oberman, Network Engineer
> > Energy Sciences Network (ESnet)
> > Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
> > E-mail: oberman at es.net Phone: +1 510 486-8634
> > Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751
Alexandre Kovalenko (Олександр Коваленко)
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