Micron/Crucial briefed us on their new M500 line of SSDs, which upgrades the controller to the Marvell 88SS9187-BLD2 along with moving to 20nm Micron MLC NAND. Along with the NAND process shrink comes higher NAND die capacity: 128Gb per die to be specific. This in turn allows Micron to bring higher capacity SSDs down to previously unheard of prices—particularly for what should be high performance, high quality SSDs. The M500 line will launch with 120/240/480/960GB models, in 2.5”, mSATA, and M.2 (formerly NGFF) form factors. Full pricing information isn’t available yet, but Micron is promising the 960GB drives will cost under $600. We’ve basically seen the same sort of drive upgrade from Plextor already with the M5 Pro, though both Plextor and Micron of course provide their own customized firmware. Note also that both the Micron and Crucial versions will use the same M500 branding, which will hopefully alleviate any confusion this time around. Here are the core specs for the four capacities.

There are a few key points worthy of note. One is that the M500 posts lower transfer rates and IOPS than the M5 Pro, though of course these are all paper specs so take them with a grain of salt. The other interesting item is that Micron is now going with more overprovisioning than on their previous model SSDs. We’ve seen the effect of spare area in our recent testing, so the move from 7% spare area (the difference between GiB and GB) to 14.5% spare area will improve the worst-case performance. Another item to note is that the 2.5” enclosures are now all 7mm thick, and they ship with a free 9.5mm adapter. All of the M500 line includes hardware AES 256-bit encryption, and Micron showed us an array of small capacitors on one of the M.2 form factor drives that supported flushing of all data to the NAND in the event of a power loss--not a super capacitor as seen in enterprise class SSDs, but there's no RAM cache to flush so it's just an extra precaution to ensure all of the data writes complete.

At this point, we’re now getting very close to the limits of the SATA 6Gbps interface, so some performance improvements over the previous generation M4 aren’t all that huge. Read speeds have improved from 415MB/s on the M4 series and write speeds are up from 260MB/s on the larger models; on the other hand, 4K IOPS almost double from 40K/50K read/write (again on the larger models), so random performance should be substantially better. Reliability has been quite good with Micron/Crucial drives over the past couple years, and the new drives will hopefully continue that legacy. Availability I believe should be Q2 2013 (Micron wasn't specific on this),  and we’ll have full performance reviews when we get samples.