Yesterday Western Digital and SanDisk announced their collaboration for hybrid hard drives (or SSHDs as they are now called). The idea behind the move is that SanDisk will supply Western Digital with iSSDs (I’ll explain what these are in a bit), which WD will then integrate with their hard drives to act as a read/write cache. The new 2.5" WD Black that was first showcased at IDF last year will be the first fruit of the collaboration, and it will also be WD’s first SSHD. WD’s approach with SSHDs is slightly different from Seagate’s. Seagate simply put a NAND package on the PCB and used their own controller manage it. SanDisk’s iSSD, on the other hand, is a standalone SSD with a SATA 6Gbps interface...