WD RE2 Green Power HDD

Western Digital recently jumped on to the green bandwagon by introducing this

hard drive that is designed to improve energy efficiency. The 1 TB hard drive is

ideal for data centers and its SATA II interface enables a data transfer rate

from drive's buffer to interface at 3 GB/sec. It has a cache memory of 16 MB,

which is half as compared to other 1 TB drives we reviewed in past (Seagate's

Barracuda ES.2 and 7200.11, and Hitachi DeskStar, all of which had 32 MB). The

bigger cache size helps in improving sequential read/writes and so is ideal in

streaming videos, data backups and other high-end applications, but that also

increases power consumption. The GreenPower drive uses Western Digital's trio of

Intelli technologies-Power, Seek and Park, which lower the power consumption

during start up, data transfer, caching and while the drive is idle. And while

other 1 TB desktop HDDs boast of 7200 RPM spindle speed, the optimum speed for

energy efficiency for this drive is calculated through its IntelliPower

technology. The RE2 GP drives are designed to operate at 4W at idle speed, which

is almost half of what other 1 TB drives consume. Likewise its average

operational power consumption is rated at 7.4W, again far less as compared to

others (see table below). The usage of such drives in data centers can result in

significantly lower power consumption, reduction in heat; all of which

ultimately translates into cost savings.

We tested the drive on an Intel Core 2 Duo based machine with 2GB RAM.

Comparing its performance with Seagate's Barracuda ES.2, which is meant for near

line storage systems, we find that the WD RE2 compromises a lot on performance

to make it more energy efficient. Looking at the graphs, you can see there's an

almost 19MB/sec difference for average transfer rate. This difference can be

attributed to sub 7200 RPM spindle speed. The performance of WD RE2 was a little

better than Seagate's ES.2 for Business Disk Winmark. But that wasn't the case

for high-end disk Winmark test, which checks the drive's throughput for high-end

applications. In this test, WD RE2 was about 18MB/sec behind what ES.2 had

achieved; the difference could be due to the ES.2 having a buffer memory of 32

MB, which is double than that of WD RE2.

RE2 consumes almost half the power as compared to other hard disk drives

Bottomline: It's ideal for data centers given

its power efficiency, but you pay more for the 'green' functionality.