Bill Davidsen wrote:
Joachim Otahal wrote:
John Robinson schrieb:
On 18/03/2010 16:45, Joachim Otahal wrote:
[...] You should take care of the temperature of the drives,
30°C to 35°C is preferred, above 35°C the lifespan goes down, over
40°C rapidly down.
Do you have a reference for this? Most drives' operating temperature
range is specified up to 55°C, sometimes higher for enterprise
drives, without any indication (apart from common sense perhaps) that
running them this hot reduces lifespan.
Cheers,
John.
About a half year ago the german publisher c't did this testing (or
reported from a big testing, cannot remember) what the best
temperature of desktop drives is. The statistic varied from drive to
drive since some are less than 5°C over room temperature, others are
15°C or more over room temperature (of course mounted behind a silent
fan which keeps the air moving, no turbine mode).
The result was that 10°C and 15°C are not good for the drives. The
"perfect sweet spot" changes from drive to drive (even within on
manufacturer), but all of them had their sweet spot somewhere around
20°C to to 35°C with variation in the range of measurement error.
Some drives has a higher failure rate at 40°C, for some 55°C was no
problem at all and showed no real change in the failure rate. The last
two examples were the extreme cases.
Some of my drives are 2°C above room temperature, others are 12°C over
room temperature. Sine I really take care that non reaches 40°C even
in summer the failure rate got down from "every few month" to once in
the 3 years which is the time I really take care of the drive
temperatures. There are 6 drives currently in use from 750GB (the
hottest of all my drives) up to 1.5 TB in my private machines, only
one of them shows a gradual change in the SMART values (reallocated
sector count), which mean it will probably fail in about 1.5 years if
the error rate stays constant. At work (at least the two machines 100%
under my control) I had the same effect, keep the HD's cool and they
will live long, let them get over 40°C and be ready to replace them soon.
40°C is a good target, readily available to people in the Arctic. It
requires a lot of cooling to do it in normal climates where the ambient
may be mid to high 40s. Fortunately my experience looks more like
Google's, as long as you move enough air over the drive to avoid hot
spots they seem to do well, hitting 43-46 much of the time. If I replace
them because they're obsolete and working, they lasted long enough.
Perhaps being "always on" is part of longevity, the ones I have on for
5-6 years seldom fail, the desktop cycled daily maybe half that.
I do note that the WD drives run about 8°C cooler than Seagate. That's
the "black" drive, I guess, the "green" drives would run cooler, based
on power use. I will switch to them next build.
I find this whole discussion of drives interesting. Thanks to everyone
for their input.
A thought occurred to me today. Realizing that the drives are generating
heat, *if* it's true that drives which run hotter have a shorter
lifetime (which is debatable), it's possible that the cause of heat
generation (friction?) is the contributing factor to the shorter
lifetime, and not the heat itself. IOW, if a drive runs hot, removing
the heat more quickly (reducing its operating temp) wouldn't necessarily
increase the drive's lifetime.
Just a thought.
--
-Eric 'shubes'
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