Typical hard drive standard improvements have brought limited performance gains at best, but the new SATA3 standard AMD and Seagate have demonstrated could change that thanks to the advent of SSD technology. SATA3 compatibility on your next motherboard purchase might be more important than in the past.
AMD and Seagate have jointly demonstrated the first SATA3 hard drive in public, and are promising compatible chipsets and shipping hard drives by the end of 2009. SATA3 will maintain full compatibility with SATA and SATA2—all current motherboards and drive cables should flawlessly support SATA3 drives, though you'll need a SATA3-compatible chipset in order to take advantage of the new standard's 6Gbps throughput.In the past, the raw throughput gained by moving from one hard drive standard to another has been relatively unimportant. An announcement that theoretical drive bandwidth had doubled from 1.5Gbps (SATA) to 3Gbps (SATA2) makes for great copy, but anyone familiar with the mechanics of a hard drive knows that standard HDD throughput typically couldn't saturate SATA, much less SATA2. The real benefit of new drive standards has typically come from those features that take second billing—thinner cables, smaller connectors, hot swappability, Native Command Queuing (NCQ), and improved power management.
The advent of SSDs, however, changes everything. Unlike mechanical drives, solid state drives are capable of saturating current transfer standards under certain conditions. This time, doubling throughput could have a noticeable impact on just how fast the drive can move data from point A to point B. Expect this to become a major marketing point once SATA3 connectors and drives become available—with the economy in recession, motherboard and SSD/HDD manufacturers are going to seize on anything they can possibly find to push new product out the door. SATA3 might not particularly matter for a modern hard drive, but that's not going to stop an OEM from pretending that it does.
Seagate and AMD demonstrated SATA3 vs. SATA2 using two Seagate Barracuda 7200.12 and AMD prototype SATA3 controllers. Test results showed the current SATA2 drive at 2.5Gbps and the SATA3 drive at 5.5GBps. Keep in mind that these test results almost certainly do not reflect (or attempt to reflect) real-world usage conditions. The 7200.12 series carries up to 32MB of onboard cache—if the test data is streamed directly out of cache, than yes, the difference between the two standards will come into play. AMD and Seagate, of course, aren't highlighting that fact.
"AMD strives to deliver platform technology that our technology partners can use to create high-performance desktop and laptop PCs," said Leslie Sobon, vice president of Product Marketing, AMD. "The new SATA 6Gb/second technology not only incorporates the best features of previous SATA generations but also includes new enhancements. This innovation enables AMD to continue to evolve its technology platforms and to develop low-cost designs that our technology partners can use to improve their own PC and laptop products."
The new enhancements Sobon refers to include improved NCQ performance and better power management/efficiency. The two companies declined to provide any numbers for either feature.
SATA3 could be the standard that allows future SSDs to hit new performance highs as well as equalize internal and external transfer speeds. USB has long been the dominant external data transfer standard—with FireWire all but deprecated and USB3 presumably carrying the high CPU usage of the USB standard series forward, eSATA(3) could emerge as the external connection of choice.
Source: ars technica