Western Digital’s OptiNAND HDDs are now available for purchase for a hefty sum of $679.99. Leveraging the OptiNAND technology as well as iNAND UFS embedded flash drive (EFD) on the PCB, these drives are based on 3D TLC UFS flash memory. These HDDs pack nine platters with a single-disk capacity of 2.2 TBs, and leverage ePMR (Energy Assisted Vertical Recording Technology). The drive heads use a more accurate three-stage drive technology, allowing a precise positioning of the read and write heads.
OptiNAND adds a number of advantages to these HDDs. Both RRO data and write operation metadata can be stored in iNAND flash memory, not only reducing the disk space occupation but also the number of hard disk read and write operations (IO number). The UFS flash memory can also store sector-level write operation data, which can optimize storage requirements and reduce ATI (adjacent track interference data) refresh times to improve performance. The SoC control chip of the hard disk is independently developed by Western Digital.
Western Digital’s Ultrastar DC HC560 and WD Gold 20TB HDDs are both rated for workloads of up to 550TB per year, and offer a five-year warranty, with a 0.35% failure rate. The drives will be limited to SATA 3.0, however. In terms of performance, Western Digital claims sustained transfer rates of up to 269MB/s and an average latency of 4.16ms. In terms of power consumption, both the 20TB HDDs draw 7W under load and 6W when ideal, a bit higher than WD’s other HDDs.
As already mentioned above, the WD Gold 20TB hard drive can now be purchased directly for $679.99. That’s significantly more expensive than the company’s predecessor WD Gold 18TB, which retails for $571.99 but should offer better performance and reliability.