SanDisk has lifted the lid on the Ultra II, a new SATA SSD that combines three-bit TLC flash with Marvell controller technology. The drive also features the second generation of SanDisk's nCache scheme, which addresses a slice of the flash as single-bit SLC NAND. This SLC cache serves as a temporary, high-speed repository for incoming writes.
TLC NAND typically has slower write speeds than flash with fewer bits per cell, so caching can definitely improve performance. Three-bit flash also has lower endurance, which nCache can somewhat mitigate by packaging small writes into larger blocks before passing them to main storage.
The Ultra II is supposed to hit 550MB/s with sequential reads and 500MB/s with sequential writes. Those are the only specifications published on SanDisk's website, but we've asked the company for more details, including the drive's endurance rating. The warranty expires after the usual three-year term.
Starting in September, versions of the Ultra II will be available with up to 960GB of storage. The top model is slated to sell for $429.99, or $0.45 per gig. Expect to pay $219.99 for the 480GB variant, $114.99 for the 240GB, and $79.99 for the 120GB.