Re: RAID Class Drives`

John Robinson schrieb:

On 18/03/2010 16:45, Joachim Otahal wrote:

quoted

[...]  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.

Joachim Otahal
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