Western Digital Caviar Green (WD30EZRS)
Western Digital is something of a pioneer in this story because its 3 TB was the first one available. Along with the previously-tested WD30EZRS, the manufacturer now provides the WD30EZRX, another drive with the same capacity. The only difference is the interface. While our test candidate uses a SATA 3 Gb/s interface, the WD30EZRX has twice the potential interface bandwidth at 6 Gb/s. Of course, as we all know, neither drive can even come close to saturating those links.
Both drives are part of the Caviar Green product line, which along with the 3 TB capacity comes in 2.5, 2, 1.5, 1, and .75 TB capacity points.
Yet again, we see another drive vendor playing the same game. Western Digital reveals nothing about the exact speed of the Caviar Green drives, just like Hitachi with its Deskstar 5K3000. Hitachi calls the feature CoolSpin, while Western Digital opts for IntelliPower. With these mechanisms, the hard drives spins at a rate that achieves the best balance of performance, noise level, and power consumption. Because the manufacturer promises that performance is in no way compromised by the IntelliPower function, you can assume that the speed is somewhere between 5400 and 6000 RPM, just like the Hitachi drive.
While the ED30EZRS makes no claims of stellar performance potential, it lives up to its stated purpose of quiet data storage. The device is by no means slow, though. Its average read throughput of 94 MB/s is nearly as fast as its most applicable competition, Hitachi Deskstar 5K3000. However, the high average access time of more than 20 ms and the comparatively low interface performance of 211.6 MB/s speak for themselves. The 7200 RPM drives (like Seagate's Barracuda XT) deliver results almost twice as fast. The Western Digital WD30EZRS also must yield to the competition when it comes to the application benchmarks.
If you're looking for a large drive for data storage or several disks for a NAS server, the Western Digital WD30EZRS is ideal. However, the competing Hitachi drive is worth its slightly higher price if you're planning to use it in large storage arrays. With an idle power consumption of 6.2 W, it uses almost 1 W less, putting it in the lead for performance per watt.