SUMMARY: High CPU temperature on a Sunfire V880

From: Craig Robinson <>
Date: Mon Jul 15 2002 - 22:49:00 EDT
Thanks to all who responded (see list below).  The range of CPU temperatures
quoted by all was between 52 and 78 degrees celsius, with an average of 63
degrees (n=17 diffrent CPU's).  I receieved a particularly good response from
Larye Parkins which I like so much that I will quote it in it's entirety:

%< snip

I have a couple of Blade 100s, which also report the CPU die temperature:
older SPARCs report "ambient" temperature on the motherboard, newer ones have
a sensor on the CPU chip, which reports higher temps, naturally.  My Blade at
work in a temperature-controlled space (68-72) shows about 65C die, 36
ambient. In our current heat wave of 38C outside temp, my home machine, which
is on the second floor of a non-air-conditioned 1915 farmhouse, shows 82C and
44C, respectively.  Silicon becomes a conductor at 105C, as I recall from my
old computer engineering days in the 70s, but the transition is quite abrupt:
we were running chips at 75-80C normal operating condition in the early 1970s,
measured on the lid, so the dies were probably higher.  I shut off my Blade
for a while last night, but after three hours, it still showed 79C immediately
after reboot, while the 'case' temp showed the room temp, about 34 degrees.
So, it seems die temps of mid-seventies to low eighties are not unheard of on
SPARC IIe and III chips, and normally run in the mid-60s in a 20C room
ambient.  The die temp rise doesn't seem to be linear with the ambient rise,
but the machine seems to be able to take whatever the operator can.

I couldn't find any Sun specs on environmental conditions, either: you would
think they would put out something, since the "die temp" has been a frequent
subject of discussion on various Sun mailing lists.

%< unsnip

Gratefully acknowledge responses from the following sun managers:

Peter Evans
John Riddoch
Bert Konijnenberg
Paul Greidanus
Larye Parkins
Paul Norton
Robert Legate

Cheers, Craig

Craig Robinson
Environmental Protection Agency
Tel: (07) 3006 4629     Fax: (07) 3247 6534

Visit us at:
sunmanagers mailing list
Received on Mon Jul 15 22:58:31 2002

This archive was generated by hypermail 2.1.8 : Thu Mar 03 2016 - 06:42:49 EST