SanDisk has announced the upcoming availability of Vaulter, a solid state memory chip that will be able to turn standard HDDs into hybrid hard drives.

The flash-based PCI express module operates in parallel with the system's hard drive, with the duty of storing and launching the operating system and user-defined applications. By doing this, Vaulter relegates the hard drive to "cold storage," where the system can draw from only when needed.

This product will come at an opportune time, when the ONFi (Open NAND Flash Interface) Working Group is about to overcome what it calls a "significant bottleneck" in NAND memory read performance. Legacy NAND interfaces are limited to a 50MB per second transmission speed, but the new ONFi 2.0 spec delivers up to 133 MB/second with infrastructure in place for later generations to reach as much as 400 MB/sec.

The 0.9 draft of the ONFi 2.0 standard is set to be released in January 2008, roughly the same time as SanDisk will begin offering Vaulter to OEMs. It will initially be sold in 8GB and 16 GB sizes.

Earlier this year, Samsung released a complete hybrid hard drive which includes an 80/160GB 5400 rpm drive supplemented with 256MB of NAND flash. The drive, given the name FlashON, was made available not only to OEMs, but also consumers by means of an optional upgrade to Samsung's 15.4" R55 multimedia notebook. The whole system retails for $1923 USD.

Vaulter, however, is simply the solid state component awaiting partnership with a hard drive. Vista users may utilize the Windows ReadyDrive feature to facilitate integration of SanDisk's product, and it could conceivably be paired with a variety of hard drive brands.

SanDisk is betting that users will likely be more willing to hybridize their current drive setup than go out and buy a complete system, which will soon become a legacy anyway.