Subject: Re: CPU temperature question...
To: Greywolf <>
From: Greg A. Woods <>
List: current-users
Date: 02/04/2002 15:07:40
[ On Monday, February 4, 2002 at 11:21:40 (-0800), Greywolf wrote: ]
> Subject: CPU temperature question...
> What's an acceptable temperature high for a CPU?  Normally, mine
> run at 36C.  During monster builds ( the temp goes up to 53C.
> BIOS default critical temperature seems to be 87C.

It depends on what CPU you've got (and thus where the temperature sensor
is mounted).

IIRC modern Intel CPUs (PIII's, and very late model PII's) have a
temperature sensor right on the CPU die.

Some older socketed-CPU motherboards though have the sensor mounted on a
little flexible film in the hole in the centre of the CPU socket, and I
guess the hope is it'll touch the underside of the chip casing.

If the sensor's right on the die then just get a copy of the chip spec
sheet and see what it has to say about operating temperatures (and how
they might be measured and how those measurements might be compared with
what the sensor might offer), and hope the sensor is calibrated half-way
decently.  I'd guess on most chips you could on average go to 100C die
temperature without causing permanent damage.  IIRC the die of most any
silicon chip will be permanently at anything over 125C.  Note though
that die temperature will be quite a bit different than the temperature
on the surface of the casing, or the heat sink.  IIRC Intel's spec
sheets give the thermal coefficients of the casing.

								Greg A. Woods

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