As the year marches on, work proceeds apace on the next big step in the Serial ATA specification. Alternately called SATA Revision (or just Rev) 3 or SATA 6Gbps, the updated specification was finalized late last year. This week at the FOSE '09 government tech show in New Orleans, Seagate is becoming the first hard drive manufacturer to publically demonstrate a SATA 6Gbps hard drive. Seagate's technology demo is in partnership with AMD, which has supplied the necessary chipsets to achieve the third-generation SATA interface's fast speeds.
The SATA spec bump is a natural evolution. Notes Seagate's Marc Norblitt, “We need to make the interface faster, so the interface doesn't become a bottleneck that causes performance to suffer dramatically. The higher the capacity of the drive, the higher the areal density; the higher the areal density, the more bits you get under the head in the same amount of time.” That, Norblitt adds, translates into data being output faster.
The read speeds that Seagate has achieved, and will be demonstrating at the show, are about 550 megabytes per second (including command overhead). By comparison, SATA 1.5 achieved 120Mbps, and SATA 3 achieved 250Mbps. The demonstration uses an AMD reference motherboard, with an AMD SATA 6Gbps chipset and CPU, and a prototype 6Gbps drive. The drive uses the same SATA connectors as current-generation SATA drives, and is backward compatible with earlier SATA versions.
Although SATA 6Gbps will be here by year's end, Norblitt says he doesn't expect the technology to be needed for another two years. When such drives do ship, they will provide a future-proofed way for individuals to plan ahead. Norblitt expects Seagate will have a SATA 6Gbps drive to market in “late 2009.” The company expects to focus on placing the drives in high performance PCs, gaming PCs, and low-end server PCs. -targeting channel. “We're targeting customers who want high capacity, high performance disc drives,” explains Norblitt.
Among the big improvements for SATA 6Gbps: Better power management, and improved native command queuing. With regard to power management, the new spec gives more control to the host or device. Instead of shutting the interface off, it allows it to into a slumber mode, one that's initiated by either the device or the host. The updated native command queuing allows streaming commands. So how will SATA 6Gbps stack up against the other forthcoming interface speed bump, USB 3.0? “SATA is a storage interface; USB is a universal interface,” Norblitt says simply. The two interfaces, he adds, will be able to co-exist.