[Beowulf] Not sure if people have seen it yet, but 2TB disks from Western Digital appear to be in the wild ...

Kilian CAVALOTTI kilian.cavalotti.work at gmail.com
Wed Jan 28 03:06:08 PST 2009


On Tuesday 27 January 2009 22:50:47 Bruno Coutinho wrote:
> It isn't a 5400rpm driver, it is multispeed with speed between 5400 and
> 7200rpm.

Well, it seems to be more complicated than that:

The manufacturer is careful in not directly citing spindle speed, instead 
nominally positioning the Caviar GP as a "7200 RPM-class" drive. Under its 
"IntelliPower" moniker, WD claims a "A fine-tuned balance of spin speed, 
transfer rate and cache size designed to deliver both significant power 
savings and solid performance." Some folks have misinterpreted some admittedly 
vague specs on WD's website. Under "Rotational Speed," the manufacturer cites 
"IntelliPower (5400 to 7200 RPM)." This does not mean the drive dynamically 
changes its spindle speed during operation... indeed, such a feature would 
entail considerable mechanical engineering and would in many ways defeat the 
point -- rapidly accelerating and decelerating the spindle's speed would 
increase rather than decrease net power draw. Rather, the IntelliPower term 
indicates that the GP family as a whole does not have a set spindle speed (nor 
a set buffer size, for that matter). Different capacity points may feature 
differing spin speeds and buffer sizes. For those that must know, WD admits 
"sub-6000 RPM operation" for the 1-TB Caviar GP.


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