How to find real CPU temperature?

[Unga]

--- On Wed, 8/5/09, Erik Norgaard <norgaard at locolomo.org> wrote:

> From: Erik Norgaard <norgaard at locolomo.org>
> Subject: Re: How to find real CPU temperature?
> To: "Unga" <unga888 at yahoo.com>
> Cc: freebsd-questions at freebsd.org
> Date: Wednesday, August 5, 2009, 7:03 PM
> Unga wrote:
> > Hi all
> > 
> > I'm running FreeBSD 7.2 on Intel P4 computer.
> > 
> > The "lmmon -i" shows 21C and when go to BIOS shows
> 65C! BIOS reading seems to be correct as the CPU heat pipe
> is very hot to the extent cannot touch.
> > 
> > How do I read the real BIOS temperature readings when
> FreeBSD is running to check whether the computer is over
> heating?
> 
> $ sysctl hw.acpi.thermal.tz0.temperature
> 
> on my computer shows 56C

Here is what it show on my computer:

sysctl -a | grep hw.acpi.thermal
hw.acpi.thermal.min_runtime: 0
hw.acpi.thermal.polling_rate: 10
hw.acpi.thermal.user_override: 0
hw.acpi.thermal.tz0.temperature: 19.0C
hw.acpi.thermal.tz0.active: -1
hw.acpi.thermal.tz0.passive_cooling: 1
hw.acpi.thermal.tz0.thermal_flags: 0
hw.acpi.thermal.tz0._PSV: 90.0C
hw.acpi.thermal.tz0._HOT: -1
hw.acpi.thermal.tz0._CRT: 90.0C
hw.acpi.thermal.tz0._ACx: 90.0C -1 -1 -1 -1 -1 -1 -1 -1 -1
hw.acpi.thermal.tz0._TC1: 4
hw.acpi.thermal.tz0._TC2: 3
hw.acpi.thermal.tz0._TSP: 60

so which is the CPU temperature, 19.0C or 90.0C? Where does it documented what hw.acpi.thermal.tz0.temperature means?

Unga