It's been about five years since Western Digital introduced the original 36GB Raptor drive. That drive used a single three-inch platter spinning at 10,000RPM. Over the years, Western Digital incrementally improved the drive, mostly by improving areal density with the 74GB version and later adding another platter with the 150GB product. This evolution culminated in the sublimely silly Raptor X, which was a 150GB Raptor with a transparent cover.
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*Review: Extremetech (
http://www.extremetech.com/article2/...88834,00.asp)*
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