Crucial’s M500 drives are handled by
Marvell’s 88SS9187 controller, for which Crucial develops its own firmware,
while IMFT 128Gb (16GB) 20nm MLC NAND dies are used throughout.
Crucial M500
The controller is connected to 16 NAND
packages in each drive (one 128Gb die per package for the 240GB, two for the
480GB and four for the 960GB). Such high-density NAND keeps down productions
costs; the 960GB works out at an incredible 38p per gigabyte, while the others
are below the 50p mark. Only Samsung’s SSD 840 EVO 1TB and Transcend’s cheap
and cheerful SSD340 manage the same feat.
Crucial M500 240GB $176.26 inc VAT
The M500’s DDR3 cache scales with
capacity, from 256MB in the 240GB model to 512MB in the 480GB drive and 1GB for
the 960GB model. It’s used mainly for page mapping, if there’s a power failure,
a series of capacitors allows any user data in the cache to be quickly flushed
to permanent storage.
Crucial M500 480GB $324.25 inc VAT
The M500 is also compatible with the
TGC Opal 2.0 and IEEE-1667 specs, enabling hardware-accelerated encryption such
as that in BitLocker. This is more secure than ATA password encryption and has
a smaller overhead than software encryption. Finally, RAIN (Redundant Array of
Independent NAND) sets aside the extra inaccessible area of the NAND for data
redundancy, providing some protection against NAND cell failures.
Crucial M500 960GB $560.36 inc VAT
Sequential read speeds are
comparatively low, capping out at 500MB/sec and leaving the drives at or near
the bottom of the charts in both tests. Write speeds don’t fare much better,
but the two larger-capacity models have a clear advantage, hitting around 430MB/sec
in AS SSD and 15MB/sec more in CrystalDiskMark, while the 240GB drive is
limited to sub-300MB/sec speeds and comes last in CrystalDiskMark. This limit
is due to the controller only being populated with two NAND dies per channel.
Single-queue-depth random speeds are
essentially identical throughout the range. With a maximum read speed of
28.7MB/sec in CrystalDiskMark, the drives are relatively poor performers here,
but they have excellent write performance. The peak of 125.4MB/sec loses only
to OCZ’s Barefoot 3 drives.
Again, there’s little separating the
three drives with high queue-depth read speeds, although the other Marvel 9187
SSDs outperform them. As for writes, the highercapacity drives hit around
300MB/sec in AS SSD and 340MB/sec in CrystalDiskMark, leaving them mid-league,
while the 240GB model comes in rather lower, with write and read speeds of
238.9MB/sec and 276.3MB/ sec respectively.
Crucial M500 structure
The drives struggle in real-world
tests although they’re bunched tightly together in PCMark 7. In the Starting
Applications test, they’re particularly low in the charts, failing to break the
90MB/sec bar. Booting Windows favours smaller capacities – the 240GB has a
respectable 12.03-second boot speed, but the 960GB takes 14.4 seconds to boot.
Iometer speed is also respectable. The higher capacities are better here, but
even the 240GB model averages 34,975 IOPS – higher than the Samsung SSD 840 Pro
256GB, but not as good as the Plextor drives.
Conclusion
At under 50p per gigabyte, the M500
drives are the best value SSDs on test (the 960GB model is even cheaper than
the OCZ Vector 150 480GB). Performance throughout could be better, and
Samsung’s victory here is clear. Still, the 240GB drive is much better than the
cheaper Transcend one and would make an excellent primary drive for a budget
SSD based system. Meanwhile, the 480GB and 960GB models would make great laptop
upgrades by bringing both speed and capacity to a single 2.5in slot, and the
encryption, redundancy and power loss protection features are added bonuses
too.
Verdict
Some nifty features and acceptable
performance, but the low cost per gigabyte is the real highlight of the M500
series.
