Company debuts second 6Gb/s SSD

At first blush, the Crucial m4 seems virtually indistinguishable from its predecessor, the Crucial RealSSD C300. After all, it’s available in the same capacity with the same Marvell 9174 6Gb/s SATA controller and same amount of DRAM cache—256MB for the 128GB, 256GB, and 512GB versions, and 128MB for the 64GB drive.

What’s the difference between the Crucial m4 and a Micron RealSSD C400? Branding.

That isn’t to say the Crucial m4 is identical to the C300. For one thing, the m4’s firmware has been substantially updated from the sometimes-flaky firmware of the C300. For another, the m4 uses 25nm-process NAND, while the C300 used 34nm NAND. Smaller-process NAND means lower cost per gigabyte (thus, cheaper SSDs), but with a slight durability hit, albeit one probably unnoticeable to the end user.

In our tests, the m4 (and every drive in this roundup) positively smoked our best-of-the-best 3Gb/s SATA drive, the OCZ Vertex 2—sustained- read and -write scores as measured by Crystal-DiskMark and AS SSD were more than twice the Vertex 2’s scores, and the m4 scored higher 4KB random reads and writes across the board, from single-queue depth to QD 32. The 256MB of cache doubtless helped the m4 in PCMark Vantage’s HDD subtest, where it posted the highest score we’ve seen from a non–PCI-E drive. The m4 doesn’t have the fastest sustained speeds, but its random-access speeds are top-notch. And 400MB/s reads and 250MB/s writes would have been unthinkably fast a couple of months ago.

The Crucial m4 represents a great implementation of the Marvell 9174 controller, and a great demonstration of the advantage of native 6Gb/s SATA.

$500, www.crucial.com