The big difference for the Crucial M4 256GB is its stellar increase in sequential read speeds. In AS-SSD
, the M4 jumped from 426MB/sec to a mighty 507MB/sec, just 12MB/sec (or 2 per cent) slower than the Vertex 3 240GB. While we haven’t fully tested the 64GB and 128GB versions of the M4, we can confirm that this increase is shared by the smaller drives too, so even the 64GB model now benefits from over 500MB/sec sequential read speeds.
Sequential write speeds for the M4 were unchanged after the firmware update, although the Vertex 3 240GB dropped in speed slightly. This was despite us performing a secure erase on the drive before starting testing - this is an issue with all SandForce 2281-based SSDs; despite coming out of the box writing data at 290MB/sec, this reduces following use and it isn't possible to fully restore this performance via TRIM or garbage collection. Most drives level off at around 250MB/sec sequential write speeds.
Single-threaded 4KB random read performance was unchanged, but single-threaded 4KB random write has improved significantly for the M4; from 79MB/sec to 113MB/sec - a 40 per cent improvement. The Vertex 3 also improved its single-threaded 4KB random write speed thanks to the v2.09 firmware, with an increase of 12MB/sec to 100MB/sec.
The Marvell controller (left) can now compete with the
performance of SandForce-based drives
In the 64-threaded 4KB random read test, speeds increased for both drives, with the M4 rising from 158MB/sec to 182Mb/sec, while the Vertex 3 jumped from 194MB/sec to 221MB/sec. With 64-threaded 4KB random writes, the M4’s performance was unchanged, while the Vertex 3 recorded a slight decrease - 235MB/sec to 215MB/sec. The likelihood of a home user thrashing a drive with 64 simultaneous write or reads is minimal, though, so more onus should be placed on the lower, single-threaded random performance.
Meanwhile, switching to the compressible performance of the ATTO Disk Benchmark
saw the M4 receive a huge increase to its 4KB sequential read speed, jumping from 169MB/sec to 286MB/sec! However, the 4KB sequential write speeds were unchanged.
With the 1,024KB transfer size, the Vertex 3’s DuraWrite technology kicked in to give the drive unchallengeable compressible sequential write speeds of 513MB/sec, with the M4 actually dipping 10MB/sec to 274MB/sec. The M4 showed its improved read speeds, though, with a boost of close to 100MB/sec - a mighty impressive jump for the price of a free firmware update.
Needless to say, the improvement to the Crucial M4 256GB’s performance is more than palpable; the 4KB sequential read speed as measured in ATTO has jumped by more than 70 per cent in comparison to when we first looked at the drive. The headline number is the jump of the sequential read speed to over 500MB/sec read, though; a fact that is sure to worry SandForce and its ever increasing stable of drive partners.
In comparison, the Vertex 3’s latest firmware is more of a performance rebalancing, with minor tweaks here and there, although its multi-threaded 4KB random read did rise over 10 percent.
The Crucial M4 is now almost as fast as a Vertex 3, as
well as being £90 cheaper
However, the numbers only tell part of the story. The Vertex 3’s headline speeds only occur with compressible workloads such as those used in the ATTO benchmark, whereas the M4 treats compressed and incompressible files the same. We’ve found that most commonly used files, such as video, audio and most game files, are already compressed, so real world performance was closer to the Vertex 3’s slower speeds (which are still very quick, as the AS-SSD performance graphs show).
However, with the two drives now on a much more level field when it comes to performance, the sheen is well and truly taken off of the SandForce 2281 drive controller; Crucial has managed to push its Marvell controller to new heights. What’s more, SandForce-based drives still have a huge price premium; a Vertex 3 240GB will currently set you back £372 inc VAT
, while a Crucial M4 256GB (which also offers a higher formatted capacity) costs £275 inc VAT
– almost £100 less!
Crucial clearly isn't messing about, and its highly aggressive pricing policy and updated firmware make it hard to argue with the Crucial M4 256GB, which should now be at the top of your SSD shopping list, regardless of whether your priorities are pricing or performance.