Plextor M6M 256GB mSATA SSD Review

Chris gives us his full thoughts on Plextor's new M6M 256GB, an mSATA SSD, which replaces the aging M5M. Should you buy it? Read on and find out.

Published
Updated
Manufacturer: Plextor
8 minutes & 49 seconds read time
TweakTown's Rating: 91%

The Bottom Line

Plextor's M6M updates the aging previous generation M5M mSATA model and sells at a solid price point. Performance wise, this is one of the better mSATA drives on the market, but go with a 2.5" 8-channel drive if possible for even more performance.

Introduction & Specifications, Pricing, and Availability

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Turn out the lights; the party is over. Well, for 2014 anyway. At the end of the year, I look back and see what products didn't get a review due to issues found during testing. I take these products, look for the latest firmware updates, put them through the ringer, and finally write them up as they are.

The Plextor M6M hit the market this past April, around the same time Plextor released the M6S 2.5". Both drives use the same Marvell 88SS9188 controller, and the same Toshiba A19 MLC flash. The specifications are nearly identical when comparing equal capacities, and both products are rated for 72TBW (66GB per day for three years).

The difference between the M6S 256GB and the M6M 256GB we're looking at today comes down to the number of NAND packages, and the number of the die per package. The M6S uses eight NAND flash packages with four 8GB die per package. The M6M 256GB that were looking at today is a mSATA product that can only hold four packages, and each package holds four 16GB die.

The Marvell 88SS9188 is a four-channel controller that was used on a handful of low-cost SSDs this past year. When first released, the M6M 256GB cost $189.99, a price we considered high at launch when comparing the M6M to other mSATA 256GB SSDs. Now, the M6M 256GB sells for $139.99, and is in a much better position in comparison to other mSATA products.

High prices aren't enough for us to hold a review up so a product has time to develop. When we first tested the M6M 256GB, it suffered from some performance issues, and had trouble with performance consistency. Since its release in April, Plextor has released several firmware updates for the M6M series. The latest firmware, released November 21, 2014, is the M6M's sixth release, and the last I plan to test... at least in 2014.

Specifications, Pricing, and Availability

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Plextor released the M6M mSATA SSD in four capacities, 64GB, 128GB, 256GB, and 512GB. All four drives use the same configuration, a Marvell four-channel SATA to flash controller, and Toshiba A19 second-generation 19nm flash. Today we're focusing on the 256GB model that is rated at 520 MB/s sequential read, and 440 MB/s sequential write speeds. The M6M 256GB rates random performance at 94,000 read IOPS, and 80,000 write IOPS.

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The M6M series has all of the new bells and whistles, like AES-256bit encryption for security, and DEVSLP for reduced power consumption and longer notebook battery life.

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Plextor has an extensive test facility used to develop new products. We saw a similar test setup while visiting Intel several months ago. The drives go through Flexstar "hot boxes," an extreme form of testing drive reliability. Also like Intel, we rarely hear about a Plextor SSD dying in the field.

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Plextor writes its own firmware, and has used Marvell controllers for many years. Several other companies have approached Plextor over the years to get firmware for Marvell controllers.

The current price of the Plextor M6M mSATA 256GB SSD is $139.99. Newegg shows the drive in the top three in price for 256GB class (240GB and 256GB) drives at this time. The M6M is also covered by a three-year warranty, and is eligible for use with Plextor's Plextool. You can read more about Plextool, Plextor's SSD utility here.

PRICING: You can find the Plextor M6M 256GB mSATA SSD for sale below. The prices listed are valid at the time of writing, but can change at any time. Click the link to see the very latest pricing for the best deal.

United States: The Plextor M6M 256GB mSATA SSD retails for $158.23 at Amazon.

Canada: The Plextor M6M 256GB mSATA SSD retails for CDN$199.45 at Amazon Canada.

Plextor M6M 256GB mSATA SSD

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Plextor has adapted the same packaging as several other mSATA SSDs venders; the drive ships in a resealable blister pack that is retail friendly. Users also receive two screws, just in case their desktop motherboard or notebook doesn't ship with them.

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Here we get our first look at the Plextor M6M 256GB mSATA SSD. There really isn't much to look at on this side. Two NAND flash packages and a DRAM package reside under the label. The label shows the model number, serial number, and the firmware on the drive when it shipped. This drive shipped with firmware 1.00, but we used version 1.06 for testing today.

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On the opposite side, we found the other two NAND packages, and the Marvell 88SS9188 controller.

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The controller has just four channels, and is different from the controller used on Plextor's M5 Pro and M6 Pro - both use eight-channel controllers.

Test System Setup and Initial Performance

Desktop Test System

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Lenovo T440 - Notebook Power Testing with DEVSLP and Windows 8.1 Pro

Nearly all of the performance tests run on the desktop system, but we use a Lenovo T440 to run the power tests. The T440 is the latest addition to our client SSD test lab, and allows us to test the notebook battery life offered by a SSD with advanced features like DEVSLP enabled.

Initial Performance Evaluation - 4-Corner and then Some Tests

Sequential Read

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Sequential Write

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Sequential 80% Read 20% Write

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Random Read

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Random Write

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Random 80% Read 20% Write

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Nothing appears out of the ordinary in our custom replacement for ATTO, other than sequential read and write tests where QD1 manages to outperform the other queue depths in a few places.

Benchmarks - Sequential Performance

HD Tune Pro - Sequential Performance

Version and / or Patch Used: 5.50

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It's not difficult for modern SSDs to reach the upper limits of SATA III when reading data from the drive. Even with a four-channel controller, the Plextor M6M 256GB is able to deliver a lot of data to the user.

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Writing data is more difficult, but the M6M does reasonably well, even though this is the only four-channel model on the chart today.

HD Tach - Sequential Write Performance after Random Writes

Version and / or Patch Used: 3.0.4.0

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After a reasonable amount of sequential and random writes to the Plextor M6M 256GB mSATA drive, we tested it with HD Tach to look for any performance loss. The drive does well for more than half of the test, but the write performance eventually drops to very low levels.

Benchmarks - Anvil Storage Utilities

Anvil Storage Utilities

Version and / or Patch Used: RC6

So, what is Anvil Storage Utilities? Anvil Storage Utilities is a storage benchmark for SSDs and HDDs where you can check and monitor your performance. The Standard Storage Benchmark performs a series of tests; you can run a full test, or just the read or the write test, or you can run a single test, i.e. 4k QD16.

Anvil Storage Utilities is not officially available yet, but we've been playing with the beta for several months now. The author, Anvil, has been updating the software steadily on several international forums, and is adding new features every couple of months.

We can use Anvil several different ways to show different aspects for each drive. We've chosen to use this software to show the performance of a drive with two different data sets. The first is with compressible data, and the second data set is incompressible data. Several users have requested this data in our SSD reviews.

0-Fill Compressible Data

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Incompressible Data

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The M6M processes compressible and incompressible data the same way. This means you will not notice a performance loss when transferring pictures, audio files, or other bits that are incompressible.

Low Queue Depth Read IOPS

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The Plextor M6M 256GB nearly reaches over 9K random read IOPS at QD1, and manages to outpace Micron's M600 256GB mSATA SSD. The M6M is also faster than the previous generation M5M in the same capacity, until we get to QD4.

High Queue Depth Read IOPS

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At high queue depths, the M6M continues to perform under the M5M, until we get to QD32, where the M6M again overtakes the previous-generation Plextor mSATA SSD.

Low Queue Depth Write IOPS

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The M6M performs well in 4K random writes but the M600 is faster at low queue depths. The M6M is an improvement over the previous generation M5M though.

High Queue Depth Write IOPS

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The high queue depth 4K random write chart again shows the M6M outperforming the previous generation M5M from Plextor, but both drives are well behind the performance coming from the Micron M600.

Benchmarks - Mixed Read / Write Workloads

Sequential Mixed Read / Write Workloads

In this series of tests, we measure mixed workload performance. We start with 100% read, and then add data writes to the mix in 10% increments until we get to 100% writes. We believe this will be the next major area SSD manufacturers will address, after performance consistency.

Sequential Mixed Workload Bandwidth

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The M5M actually performed a bit better on the write end of the scale (right side) than the M6M model in our preconditioned sequential mixed workload test. With the drives conditioned like this, the M6M writes at the slowest rate of the drives that actually finished the test.

Sequential 80% Read / 20% Write Bandwidth

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Two drives failed the twelve-hour test. In the 80% read 20% write section, the M6M actually performed a bit better than the M5M and the BP4e. Sandforce controllers dominate this test though. We use 50% entropy (incompressible data), so SandForce doesn't have an advantage from the test; the SF-2281 is just able to perform very well with mixed workloads.

Random Mixed Workload Response Time

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In this test, we use 50% reads and 50% writes while testing with random data. The M6M does well here, but the M600 does very well.

Benchmarks - PCMark 8 Standard Storage Test

Version and / or Patch Used: 2.0.228

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None of the drives on today's charts are built for extreme workloads. Instead of running the deep test, we just ran the normal consumer test.

Final Thoughts

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Plextor needed to replace the M5M since the supply of Toshiba 19nm flash dried up when Toshiba switched to A19 production. At the same time, Marvell released a new four-channel controller that allowed Plextor to reduce construction costs on its mSATA product line. mSATA SSDs don't have enough surface area to run all eight channels to begin with, so it makes sense to use a lower price four-channel controller to start with. That's why we don't see a large performance difference between the M5M and M6M; both are running with four-channels, even though the controller in the M5M can run with all eight-channels when configured to do so.

As we mentioned in the review, none of the drives tested today were built for extreme consumer or prosumer workloads. The best use cases for mSATA SSDs is in notebooks used for surfing the web, running applications, and if you want to push things, editing a digital video from time to time. Slow conditions occur when you write a lot of data to the drives in the chart today in rapid succession. The wear leveling schemes of these products are not able to recover fast enough if you really push the drives with heavy IO. Most of us don't push enough data to slow modern mSATA SSDs, but if you do write a lot of data each day you may want to stay with a full-size SSD that provides all eight-channels.

We're glad we waited to publish this review. It not only gave Plextor time to sort out some issues, but the M6M 256GB has a much better price now. When released, the price was out of balance with other mSATA SSDs on the market, but now the M6M 256GB is only trailing a mSATA model from Transcend with an unknown controller, and the Samsung 840 EVO 250GB. The M6M performs a bit better with extended write operations since the 840 EVO quickly drops to 3-bit per cell write speeds after the TurboWrite cache feature fills.

That makes the M6M one of the best mSATA products available today, and at the same time, it has a reasonable price.

PRICING: You can find the Plextor M6M 256GB mSATA SSD for sale below. The prices listed are valid at the time of writing, but can change at any time. Click the link to see the very latest pricing for the best deal.

United States: The Plextor M6M 256GB mSATA SSD retails for $158.23 at Amazon.

Canada: The Plextor M6M 256GB mSATA SSD retails for CDN$199.45 at Amazon Canada.

Performance 92%
Quality including Design and Build 92%
General Features 90%
Bundle and Packaging 88%
Value for Money 91%
Overall 91%

The Bottom Line: Plextor's M6M updates the aging previous generation M5M mSATA model and sells at a solid price point. Performance wise, this is one of the better mSATA drives on the market, but go with a 2.5" 8-channel drive if possible for even more performance.

PRICING: You can find products similar to this one for sale below.

USUnited States: Find other tech and computer products like this over at Amazon.com

UKUnited Kingdom: Find other tech and computer products like this over at Amazon.co.uk

AUAustralia: Find other tech and computer products like this over at Amazon.com.au

CACanada: Find other tech and computer products like this over at Amazon.ca

DEDeutschland: Finde andere Technik- und Computerprodukte wie dieses auf Amazon.de

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