We first looked at SandForce-controlled SSDs last year. The company's innovative new controller could compress and decompress data on the fly, unlike other SSD drive controllers, which wrote data in a 1:1 ratio. However, SandForce-based SSDs could only achieve their top-rated speeds with highly compressible files, and offered lower real-world performance. They still delivered the increased performance you’d expect from an SSD, but we found the Marvell-based Crucial C300, which wrote data at a 1:1 ratio and still delivered stellar speeds, the better option.
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A year later, SandForce is back for round two. SATA 6Gbps drives such as the Crucial M4 and Intel 510 series still use variants of the Marvell 9174 drive controller, so there’s an opportunity for SandForce to gain the upper hand. OCZ is SandForce’s preferred drive partner, so its Vertex 3 drives are the first to market, boasting rated sequential speeds of 550MB/sec read and 520MB/sec write for the 240GB version.
With these much improved rated speeds, the Vertex 3’s SandForce SF-2281 drive controller is a significant upgrade over the last generation. It brings a SATA 6Gbps interface and support for various new NAND standards, including 25nm NAND and slightly slower asynchronous NAND, which you'll find in the OCZ Agility 3 range of SSDs.
OCZ produces two versions of the Vertex 3 – the standard one we're looking at here, and a MAX IOPS version that offers improved random read and write speeds. As the Vertex 3 is the first second-generation SandForce-based drive, it officially uses beta firmware, although SandForce has approved it for sale and the drive was stable in our tests. OCZ has a great history with new drive firmware, and we’re confident that this will continue when the Vertex 3’s retail firmware arrives.
The 240GB version of the Vertex 3 uses 16, 16GB 25nm NAND modules
The SF-2281 controller can address eight NAND channels, each equipped in this 240GB drive with two 16GB 25nm Intel NAND chips. The MAX IOPS version uses more expensive 32nm Toshiba NAND alongside a tweaked firmware, but it's otherwise identical.
Despite 256GB of on-board NAND, the Vertex 3, like the Vertex 2 before it, is aggressively over-provisioned - where a spare area of NAND contains dedicated blocks ready for writing, and to replace defective NAND automatically. Its formatted capacity is 223.5GB, with 13 per cent of the drive sidelined for over-provisioning and SandForce’s on-board error correction system.
Interface: SATA 6Gbps Nominal capacity: 240GB Formatted capacity: 223.5GB Controller: SandForce SF-2281TB1 Cache: none Memory type/amount: 16x Intel 16GB 25nm NAND flash Warranty: Three years