Plextor M5 Pro 256GB SSD review
Some companies make a real song and dance about the launch of a new product, others just seem to launch something without hardly making a ripple. Plextor sits firmly in the latter category, which is something of a surprise considering its latest Pro SSD range, the M5 series, features not one but two new technologies that are, quite frankly, worth making a song and dance about.
Tech tonic: Plextor's M5 Pro 256GB SSD
At the heart of the M5 Pro is Marvell’s latest third generation SSD controller, the 88SS9187-BLD2, code named ‘Monet’. The M5 Pro may not be the first drive to use the controller – there’s a very strong rumour that this is the silicon that lies under the Everest 2 branding in OCZ’s Vertex4 and Agility4 drives – but it’s certainly the first that doesn’t hide the fact it’s using it.
The controller is powered by a dual-core Marvell 88FR102 V5 CPU supporting up to eight NAND flash channels via an ONFI (Open NAND Flash Interface) 2.0/Toggle interface. The interface can support up to 200MB/s per channel. For cache purposes the 88SS9187 supports DDR2-800 and DDR3-800 up to a maximum of 1GB of memory for mapping algorithms.
The feature list for the 88SS9187 includes a high performance 128-bit ECC engine that relies on an adaptive read/write scheme; an on-chip RAID technology, which uses firmware algorithms to optimize retiring of defective NAND block and dies, and 256-bit AES data encryption. It also supports TRIM, S.M.A.R.T and NCQ.
Marvell controller chip block diagram
Along with the controller, the other first for the M5 Pro series is the type of NAND flash it uses – Toshiba’s latest 19nm Toggle MLC NAND. Each of the three capacities of M5 Pro’s come with eight NAND modules, the difference between them being the number of 8GB dies per module; two (making them 16GB parts) in the case of the 128GB drive, four (32GB) in the 256GB drive and eight (64GB) in the 512GB drive.
The M5 Pro I’m looking at is the mid-range 256GB (PX-256M5P) model. It has a quoted Sequential Read speed of up to 540MB/s which is the same for the 128GB flagship 512GB capacity drives. The Sequential Write speed for the 128GB drive is up to 340MB/s and up to 450MB/s for both the 256GB and 512GB models.
CrystalDiskMark results: Compressible data scores on right
Once inside Plextor’s now familiar brushed aluminium finish metal case, the 7mm format M5 Pro is revealed in all its glory. The eight Toshiba NAND (TH58TEG8D2JBA8C) chips are on one side of the PCB, along with a pair of 256MB Nanya DDR3-133 chips making up the drive's 512MB of cache. The controller sits all on its lonesome on the other side of the board.
When the drive was tested with the ATTO benchmark, it gave a Read performance of 545MB/s – a tadge over the officially quoted figure of 540MB/s, while the Write performance was a bit shy of the quoted 450MB/s at 418MB/s.
AS SSD and ATTO results
Unlike LSI SandForce controlled drives, the Marvell silicon in the M5 Pro has no problem dealing with compressible data, as can be clearly seen by the two sets of CrystalDiskMark benchmark scores. These show hardly any difference between the Write performances in either of the two modes. It’s the same story in the AS SSD benchmark; the default in-compressible test produces Sequential Read/Write scores of 500MB/s and 430MB/s respectively. Switching to AS SSD’s compressible data test, the drive doesn’t miss a beat producing a Read score of 504MB/s and Writes of 450MB/s.
Plextor’s M5 Pro is the first of the next generation of SSD’s officially using the latest Marvell silicon to break cover. Not only that, but it also uses the latest in NAND technology as well. Under test conditions its headline Write performance was a little lower than the official figures, but no doubt there is a firmware upgrade on the way to improve this. Yet as it stands, it’s still a very quick drive out of the box and Plextor has been bold enough to back it with a 5 year warranty. ®
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