SATA Express ports have been available on select 9-series motherboards since last spring. Drives designed for the new standard have been scarce, but WD is demoing a prototype at the Storage Visions conference occuring during the CES festivities in Las Vegas. The SATAe hybrid combines a 4TB mechanical hard drive with up to 128GB of solid-state storage in a standard 3.5" form factor.
The demo unit is equipped with 64GB of flash, and WD claims it delivers "near-SSD performance" in the PCMark 8 benchmark. That score was achieved with the integrated SSD configured as a cache for the mechanical component. TweakTown adds that the hybrid can also be used in a dual-drive config, with the solid-state and mechanical drives treated as separate entities. That dual-drive config is reminiscent of WD's Black², which marries mechanical and solid-state components in a smaller 2.5" form factor (and with a traditional Serial ATA interface).
PC enthusiasts have been rolling their own dual-drive setups for years, but combining the components in the same form factor has some benefits for larger system builders. As WD's senior VP of engineering Gary Meister points out, the hybrid approach "[frees] up one slot in the system and [simplifies] how our customers could create and maintain such an advanced storage solution." SATA Express simplifies things further by providing a single interface that offers sufficient bandwidth for speedy SSDs and backward compatibility for existing SATA hardware.
WD's press release doesn't indicate when the SATAe prototype will be ready for prime time, but it pegs the cost-per-gig in the same range as current desktop SSHDs, which sell for around $0.04/GB.