Until very recently the only 2 TB hard disk drives available on the market were “green” models, rotating at lower speeds in order to save energy, like Seagate Barracuda LP and Western Digital Caviar Green. Western Digital has finally released two 7,200 rpm models, Caviar Black (targeted to desktops) and RE4 (targeted to servers). Let’s take a look on the performance from these new drives.

Hard drives typically consume between 8-10 W; “green” models consume practically half of this. The trade-off is obviously performance: since they rotate at lower speeds “green” drives present lower performance. Drives from this category are mainly targeted to external enclosures that are going to be connected to the computer thru a USB or FireWire port. Since this kind of port limits the drive performance, the hard disk drive doesn’t need to be the fastest around and thus you can save money both on the cost of the drive and on your electricity bill.

Drives targeted to the enterprise segment (i.e., servers), on the other hand, have a higher reliability, as required for this market segment, with some manufacturers providing extended warranty contracts with the drive. With some enterprise-class drives, for example, the manufacturer can ship a new drive in case of failure before the client sends the defective drive to them, reducing the down time of a server.

2 TB hard disk drives have a real capacity of 1.82 TB or 1,863 GB (3,907,029,168 sectors). As you may be aware, the capacity advertised by hard disk drive manufacturers isn’t the real drive capacity. Read our Hard Disk Drives Capacity Limits tutorial for further information on this subject.

Here is a summary of the hard drives we are going to compare:

Western Digital does not inform at what speed their Caviar Green drives spin; 5,400 rpm is our educated guess.

Prices were reasearched at Newegg.com on the day we published this review. We couldn’t find Western Digital Caviar Black 2 TB being sold yet.

Seagate announced last week the launch of their first 7,200 rpm 2 TB hard drive, Barracuda XT, which is based on the new SATA-600 interface, doubling the available bandwidth. All the other drives are based on the SATA-300 interface. We will post a review for Barracuda XT as soon as it becomes available.

Now let’s compare the performance from these four 2 TB drives.