OCZ Technology unleashes 4th-generation PCIe-based SSD: 512Gbytes to 2Tbytes

Yesterday, high-performance PC component developer and vendor OCZ Technology rolled out its 4th generation of PCIe-based SSD drives called the Z-drive R2 SSD. The new drives employ NAND Flash memory DIMMS arrayed on a standard PCIe-format add-in card. The cards employ x8 (8-lane) PCIe interfaces to achieve a rated read speed of as much as 1.3Gbytes/sec for the 512Gbyte SSD board and 1.4Gbytes/sec for the 1Gbyte and 2Gbyte SSDs. Peak write speeds for the drives are 1 and 1.4Gbytes/second respectively and sustained write speeds are 550 and 950 Mbytes/sec respectively. The purpose of using PCIe interfaces rather than the industry standard SATA interface for SSD interconnect is to bypass the limitations built into the SATA interface standard and protocol due to the assumptions made about rotating memory that are baked into the SATA protocol. Instead of being limited to 1.5 or 3 Gbits/sec interface speeds and the protocol overhead incurred when dealing with rotating memory, an 8-lane PCIe interface supports bidirectional, simultaneous read and write transfer speeds of approaching 4 Gbytes/sec, about an order of magnitude faster than SATA. In fact, OCZ’s press release states: the “ Z-Drive R2 SSD maximizes bandwidth by taking the SATA bottleneck out of the equation and utilizes the speed advantages of the PCI-Express interface.“

The higher speed of the larger OCZ SSDs arises from the additional parallelism of the additional NAND Flash DIMMs added to the board to increase capacity. So it’s clear that OCZ has employed a Flash controller that understands and can exploit the additional parallelism provided by the extra NAND Flash DIMMs. A 1-million-hour MTBF suggests that the Z-Drive R2 SSD’s on-board controller is also carefully monitoring the health of the on-board NAND Flash and is performing appropriate wear leveling as well.