WD Scorpio Blue 5400 RPM 2.5-inch SATA hard drives from Western Digital deliver lightning-fast and ultra-quiet performance hand-in-hand with low power consumption. In addition, they are designed with ruggedness, reliability, and data-protection features that actively watch over valuable data. Available in capacities from 160 to 640 GB, these drives feature a 3 Gb/s SATA interface and 8 MB cache. WD Scorpio Blue hard drives are designed for portable digital devices of all kinds, including notebook computers, external storage, and digital media players.WD Advanced Format technology increases media format efficiency, thus enabling larger drive capacities. WD Advanced Format drives are specifically optimized for Mac and the latest Windows operating systems such as Windows Vista and Windows 7. WD Advanced Format drives work with legacy operating systems such as Windows XP but require the use of the free WD Align software.