Conclusion

Western Digital is very late to the Solid State Hybrid Drive (SSHD) market. Seagate launched the industry's first SSHD, the Seagate Momentus PSD, back in 2007. It has taken Western Digital 8 years to dip their toes into SSHDs, and we are glad to see that they are off to a good start.

Like all other SSHDs, the 4 TB Western Digital Blue (WD40E31X) SSHD uses a small 8 GB SSD as a fast secondary cache, in addition to the usual SDRAM cache.

This flash memory cache quickly stores all writes to drive, copying them over to the slower hard disk drive over time. Because it retains the written data, the data can be read from the flash memory cache. This improves its read performance, albeit only for the data that is stored in the cache.

Thanks to its flash memory cache, the 4 TB Western Digital Blue SSHD was actually faster than the 6 TB Western Digital Black in the Business Disk WinMark test. This is very impressive as the 6 TB Western Digital Black is a very fast 7200 RPM hard disk drive with higher-density platters and a very large 128 MB DDR3L SDRAM cache.

When we compared the Western Digital Blue SSHD to its regular WD Red counterpart, it proved to be 3x faster in small random writes, more than 2x faster in large random writes and 35% faster in large random reads. Only its small random read performance did not benefit from the flash memory cache.

The 4 TB Western Digital Blue SSHD also enjoyed a small boost in its sequential read and write performance. However, it was more limited due to the relatively limited performance of the 4-channel JMF608 flash controller, which is limited to 150 MB/s (read) and 100 MB/s (write). Western Digital should use a faster flash controller if they want to maximise the performance of their future SSHDs.

The 4 TB Western Digital Blue SSHD is no SSD, but it offers pseudo-SSD performance in the performance aspect that the hard disk drive is weakest at - random accesses. That's why it "feels" like you are using an SSD. Even though it's not quite as fast as a real SSD, it comes with an enormous storage capacity and costs far less per GB.

The 4 TB Western Digital Blue SSHD is best used as a large capacity boot drive for gaming systems or desktop computers, where its SSD cache will speed up reads and writes. It is also a great upgrade option for older computers - it will give them a new lease of life, thanks to its significantly better performance and storage capacity.

For the lowest current prices on the Western Digital Blue SSHDs, click here!

Support Tech ARP!

If you like our work, you can help support out work by visiting our sponsors, participate in the Tech ARP Forums, or even donate to our fund. Any help you can render is greatly appreciated!

Questions & Comments

Please feel free to post your questions or comments here!