Western Digital Caviar Green WD20EARS 2TB SATA Hard Drive

Western Digital Green Desktop SATA Hard Drive

Western Digital

Western Digital has discontinued production of the Green model hard drive instead of using the green name for their new line of solid state drives. It is still possible to find these older Green hard drives. You can also check out the Best SATA Hard Drives for a list of other currently available hard drives.

The Bottom Line

For anyone looking to add a large amount of storage to their desktop computer or just have a drive that produces very little noise or heat, the Western Digital WD20EARS 2TB SATA drive is a solid choice. While its performance is not suited for those wanting high performance, it does a great job as a secondary storage or backup drive. Performance is still good all while being very quiet and cool to the touch. It also offers some a great price per gigabyte. The downside is that the drive is not suited for use in RAID arrays and the three-year warranty is less than some of the competition or Western Digital's own Caviar Black series.

What We Liked

  • Large Storage Capacity
  • Good Price Per Gigabyte
  • Runs Very Quiet and Cool

What We Didn't Like

  • Not Suited for RAID Usage
  • Three Year Warranty Less Than More Expensive Drives or Some of the Competition


  • 2TB (1.81TB Formatted) Storage Capacity
  • 3.5-inch Internal Desktop Form Factor
  • Variable Rotational Speed
  • 64MB Cache
  • SATA 3.0 Gbps Interface
  • 24dBA/29dBA Idle/Seek Acoustics
  • 4.5W Read/Write, 2.5W Idle, .7W Sleep/Standby Power Consumption
  • Three Year Warranty


Western Digital's Caviar Green series of drives are designed for high capacity and low power consumption. In fact, the largest drives that are available for desktop PCs tend to be sold among the green class of drives. The WD20EARS may not be the highest capacity drive on the market, but it is an important capacity because many older desktop computers and operating systems can't properly handle drives larger than 2TB. As a result, this is the best capacity choice for those with older computers but it also works well for those with new computers who need some serious storage space. And with prices as low as $80, this makes for a very good price per gigabyte.

In order to achieve the low power consumption and lower operating noise and heat levels, green class drives typically have to sacrifice performance. This is primarily achieved through lower rotational speeds. In the case of the Caviar Green series, the rotational speed starts out around 5900rpm which is well below the standard 7200rpm rate. Now, Western Digital has implemented a variable speed system they call IntelliPower. This means that the drive will ramp up the rotational speed when the hard drive is having consistent usage. It then spins back down to the lower levels when idle to reduce the power and noise levels.

One key to note about the WD20EARS version of the drive is the Serial ATA interface. This drive uses the SATA II or 3.0Gbps interface speeds. Western Digital also makes a version that uses the new SATA III or 6.0Gbps interface. Why does this matter? Well, hard drives don't really require the faster interface as the mechanical properties restrict the overall performance of the drives. In fact, in testing, the highest burst rate of the drive was 176MB/s which is well below the 375MB/s maximum supported by SATA II. As a result, consumers can save a bit by going with this version over the WD20EARX or SATA III version.

As for the overall performance of the drive, it is actually quite good for a green class drive. As mentioned before, it can burst up to 176MB/s with average rates just below 100MB/s. The reason this can be achieved is the higher density of the drive platters on the Green drives compared to the faster drives with lower capacity. It still isn't going to load the OS, programs or data as quickly as a performance drive but it gets the job done. The best part is that the drive under heavy load runs very cool. This is great if the drive will be installed into an external enclosure or in a case that has limited airflow.

Overall, the best uses for the Caviar Green 2TB drive is as a secondary or backup drive. The high capacity will allow it to store a large amount of data. This is perfect for things like digital media files as they don't require the fastest read speeds in order to be properly utilized. Similarly, backups tend to be slowed down by the management and compression so it will work just as well as higher performance drives that cost more.

One important thing to note about the Caviar Green drives is that they are not suited for RAID usage. The reason is that the variable speeds of the drive can cause the multiple drives to become desynchronized that can lead to data corruption. So it is best to stick to lower capacity fixed speed drives if you want to create a high capacity drive array.