May 17, 2010
Serial ATA 6Gb/s – The Third Generation
by Ryan Morse – May 16, 2010
In this Tech Tip I'll go over what you need to know to decide when the right time is for you to upgrade.
What's In A Name?
It turns out that what's in a name is understanding. A rose by any other name could be just as sweet, but how would you know how fast it is compared to other roses? There was some confusion regarding how to officially refer to the previous two standards. You would see SATA I and SATA II as well as Serial ATA 1.5Gb/s and Serial ATS 3Gb/s used interchangeably. Naturally, with this third revision to the specification coming out, it was important for the Serial ATA International Organization (SATA IO) to get the correct terms out there. First and foremost, the Roman numeral representations of the standards are incorrect, especially SATA II, as this is the old name for the organization that created the standard. Additionally, using that nomenclature the new standard would be called SATA III and would be spoken as, "S-A-T-A Three," which can easily be confused as SATA 3Gb/s. So, while it is a mouthful, the Serial ATA IO prefers you say the entire transfer rate of the standard to avoid any confusion.
The biggest and most obvious improvement in the third generation of the interface is the 6.0 Gb/s transfer rate, which translates to 768 megabytes per second, about as much data on a CD-ROM. With protocol overhead, you're likely to see real-world transfer speeds of roughly 600 megabytes per second. The new standard calls for twice the throughput as the second generation and is geared toward streaming high-definition content and high-capacity flash memory devices like solid state drives. To aid in this task a streaming command was added to the Native Command Queuing technology already utilized in existing Serial ATA drives. Native Command Queuing, simply known as NCQ, is the method Serial ATA drives use to organize read and write requests efficiently. Now, with the streaming command as well as NCQ Management for optimized performance, the third generation stands to provide noticeable improvements in operation, with the biggest improvements seen in SSDs (Solid State Drives). Serial ATA 6Gb/s is also compatible with the previous generation, Serial ATA 3Gb/s, unfortunately, it's not compatible with the first generation standard, Serial ATA 1.5Gb/s.
How Do I Get It?
The two ways to get this new technology remain the same as with most I/O technologies, you can install an add-on card or buy a motherboard with it already integrated. There are a number of affordable PCI Express add-on cards, even some with SuperSpeed USB 3.0, too, but you'll need to be PCI Express 2.0 compliant to enjoy the best performance on existing hardware. Buying a motherboard with integrated Serial ATA 6Gb/s is the other option available, but there are only a handful of boards and devices in the market right now. It is likely to remain this way until Intel releases it as an integrated solution in their desktop boards in Q1 of 2011. Until then, widespread adoption is unlikely and you will see the slow trickle of SATA 6Gb/s devices, add-on cards, and motherboards continue. Soon after you'll be able to purchase it in fully-built systems from OEM manufacturers like HP, Gateway, Dell, and the like. Who knows? Maybe the next generation of Macbooks will have it, too!