SATA-IO, the International Organization that owns and manages Serial ATA specifications has announced SATA 3.2 which paves the way for faster SSDs. The latest specification includes SATA Express, a new specification that enables the coexistence of SATA and PCIe storage devices, as well as enhancements in power management, new SATA form-factors, and optimizations for solid state hybrid drives (SSHDs).
ATA Express works by using up two lanes of PCI Express and allow up to 2 GB/s of bandwidth. While standard SATA 3 has a maximum bandwidth of 0.75 GB/s.
PCIe was usually mostly used for graphics cards and other expansion cards but recently some manufacturers have started to release PCIe SSDs. With the SATA Express specification it's possible for SATA and PCIe solutions to coexist. SATA Express is not really a new interface however, it's mainly a new connector.
This new connector makes it possible to connect SSDs in regular formfactors, like 2.5" drives to the PC. The SATA Express connector has two PCI-Express lanes. When PCI Express 3.0 is used this means a maximum bandwidth of 2 GB, triple the amount of SATA-3.
However the SATA Express connector is backwards compatible with SATA. When connected on a PC that doesn't support SATA Express, a future SSD will still work through the SATA interface. If connected to the SATA interface the drive will also only have the SATA-3 bandwidth available. When connected to a PCIe interface, the drive will work at full speed.
The new connection is also mechanical compatible. This means that you can connect a SATA Express SSD with a regular SATA cable on a current SATA controller. For the PCI Express connection the same pins are used in the connector. Through a special signal the controller and drive decide whether they'll use the SATA or PCI Express interface.
Besides SATA Express the SATA 3.2 specifcation has other new features. One of them is microSSD which is a standard for embedded solid state drives that enables developers to produce single-chip SATA implementations for embedded storage applications.
Universal Storage Module (USM) enables removable and expandable storage for consumer electronic devices. SATA revision 3.2 introduces USM Slim, which reduces module thickness, allowing smaller removable storage solutions.
The specification also introduced a new power management level called DevSleep that makes it possible to nearly completely shut a drive down, to meet the requirements of new always on, always connected mobile devices such as Ultrabooks.
Another new feature is Transitional Energy Reporting which provides the host with detailed information about the SATA storage device, facilitating better power management and for RAID lovers, there's Rebuild Assist which should speed up the data reconstruction process in RAID configurations. The new Hybrid Information feature provides a mechanism in which the host can communicate data caching information to the drive, improving solid state hybrid drive (SSHD) performance.
When drives using this specification will become available is unclear.
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