Would you believe it's been nearly two years since we took our first look at Crucial's m4 solid-state drive? That's an eternity in the PC world, and the drive is long overdue for a replacement. As luck would have it, Crucial and parent company Micron have one waiting in the wings. Their new M500 SSD is due to hit shelves this quarter.
Micron is one of the biggest producers of flash memory in the industry, so it's no surprise the M500 uses chips produced in-house. The drive's MLC NAND is fabbed on a 20-nm process, just like the flash found in the Intel 335 Series SSD released toward the end of last year. Intel and Micron share a joint flash venture called IM Flash Technologies, so the chips are likely coming from the same production lines.
Smaller fabrication processes allow more dies to fit onto each wafer, which can help to lower costs. Crucial seems intent on passing the savings onto consumers, because the 960GB version of the M500 is due to sell for less than $600—under $0.63 per gigabyte. To put that figure into perspective, consider that SSDs around the terabyte mark typically sell for $1,000 and up.
The 960GB version of the M500 will be limited to the drive's 2.5" incarnation, which will also be available in 120, 240, and 480GB flavors. Those smaller capacities will be offered in ultrabook-friendly mSATA and NGFF-based M.2 form factors, as well.
Mobile systems seem to be the focus for the M500, which features an adaptive thermal throttling mechanism that should prevent overheating in cramped quarters. Crucial claims the drive consumes only 5 mW while sleeping and 150 mW when active, so there shouldn't be too much heat to worry about. Notebook users should also appreciate the fact that the M500 is supposed to wake up from sleep mode in just 0.2 seconds, five times faster than the previous generation.
Marvell provided the 88SS9174 controller silicon for the Crucial m4, and the M500 uses a newer version dubbed the 88SS9187. The updated chip has eight NAND channels and supports hardware-accelerated AES encryption. To that, a collection of tiny capacitors has been added in order to protect against data loss from power failures. Based on the capacities listed, it looks like the M500 has more overprovisioning than the m4, which came in 128, 256, and 512GB models. The flash capacity that's been skimmed off the top could be used to improve performance, create a larger pool of spare NAND cells to extend drive life, or store parity data for a RAID-like die redundancy scheme.
The M500 is rated to endure 72TB of writes over its lifespan. That's 40GB a day for five years, which seems sufficiently generous. The drive's warranty coverage runs out after three years, though.
|Capacity||Max sequential (MB/s)||4KB random (IOps)|
On the performance front, the M500 SSD is rated for top sequential read and write speeds of 500 and 400MB/s, respectively. That read speed is identical to what's quoted for the m4, but the maximum write rate is a fair bit higher than the 260MB/s listed for Crucial's fastest last-gen drive. Of course, the M500 240GB model tops out at only 250MB/s, so you have to spring for one of the larger models to enjoy optimal performance. The 480 and 960GB variants are also the only ones to reach 80k IOps with 4KB random I/O. At least in that front, the 240GB model's random I/O performance exceeds the 45-50k peak IOps of the old m4.
Retail consumers will see the M500 as a Crucial drive, but the same product will be sold to PC makers under Micron's name. The 2.5" version is scheduled to hit the market first, followed by the mSATA and M.2 variants. If the per-gigabyte cost ends up being as low as Crucial says, this could be a very appealing SSD for desktops and notebooks alike.