Continuing our spring full of SSDs, the next drives under the scope are Plextor's M6S and M6M. Both drives were already showcased at CES this year but after a series of delays the release was pushed to April, which brings us to this review. Similar to the M5 series, the M6S is Plextor's mainstream offering with a focus on price, whereas the M6M is the mSATA variant of the M6S. The M5M was actually derived from the M5 Pro, so in this regard Plextor has slightly modified their strategy but I'm guessing this is to make the M6M more competitive in price. There will be an M6 Pro as well later this year and we'll probably know more after Computex (Plextor said June/July).

Photography by Juha Kokkonen

The biggest changes the M6S and M6M bring is Marvell's 88SS9188 controller and Toshiba's second generation 19nm MLC NAND. I'll cover the NAND in more detail in just a bit but the 9188 controller is essentially a "lite" version of the 9187 found in drives like the M5 Pro and Crucial M550. The amount of channels has been cut from eight to four, which is typical for budget and low power designs. We saw a similar trend with Marvell's previous generation 917x controllers where the 9174 was the full blown 8-channel design with 9175 being the cut down derivative. I believe the main market for the 9188 is mSATA drives because the spec only allows four NAND packages anyway, but Plextor has decided to use the 9188 controller in both the M6S and M6M.

Plextor M6S Specifications
Capacity 128GB 256GB 512GB
Controller Marvell 88SS9188
NAND Toshiba A19nm MLC
Cache 256MB 512MB 768MB
Sequential Read 520MB/s 520MB/s 520MB/s
Sequential Write 300MB/s 420MB/s 440MB/s
4KB Random Read 88K IOPS 90K IOPS 94K IOPS
4KB Random Write 75K IOPS 80K IOPS 80K IOPS
Endurance 72TB (~66GB/day)
Warranty Three years

In terms of performance, there isn't any noticeable difference between the M6S and M6M. Similar to Crucial, Plextor is using 64Gbit die in the smaller capacity drives (see the table below for details) and 128Gbit in the larger ones. I covered this in the M550 review but in short the usage of smaller die increases parallelism, which in turn increases performance. For small drives the 128Gbit die is too large in capacity and the limited parallelism would lead to slow write speeds as we saw with the M500.

Plextor M6M Specifications
Capacity 64GB 128GB 256GB 512GB
Controller Marvell 88SS9188
NAND Toshiba A19nm MLC
Cache 128MB 256MB 512MB 768MB
Sequential Read 520MB/s 520MB/s 520MB/s 520MB/s
Sequential Write 160MB/s 340MB/s 440MB/s 440MB/s
4KB Random Read 73K IOPS 90K IOPS 94K IOPS 94K IOPS
4KB Random Write 42K IOPS 76K IOPS 80K IOPS 80K IOPS
Endurance 72TB (66GB/day)
Warranty Three years

Unfortunately, there is no hardware encryption support. This seems to be a feature that only a few manufacturers consider important for client drives, although I disagree because the value of the data we are carrying around is constantly increasing.

  M6S M6M
Capacity 128GB 256GB 512GB 64GB 128GB 256GB 512GB
# of NAND Packages 8 8 8 4 4 4 4
# of Die per Package 2 x 8GB 4 x 8GB 4 x 16GB 2 x 8GB 4 x 8GB 4 x 16GB 8 x 16GB

There is no NAND level redundancy either, which is also becoming a standard. The need for redundancy of course depends on the NAND and its reliability, but as we move to smaller lithographies it'll certainly be important to have some level of protection against page/block level failures. Plextor does have fairly strict quality control, though, as every drive is tested for at least 48 continuous hours including idle and power cycling tests (which are often what causes issues). Such rigid testing can make NAND redundancy less needed but I'd still like to have at least some redundancy just in case.

Test System

CPU Intel Core i5-2500K running at 3.3GHz
(Turbo and EIST enabled)
Motherboard AsRock Z68 Pro3
Chipset Intel Z68
Chipset Drivers Intel + Intel RST 10.2
Memory G.Skill RipjawsX DDR3-1600 4 x 8GB (9-9-9-24)
Video Card Palit GeForce GTX 770 JetStream 2GB GDDR5
(1150MHz core clock; 3505MHz GDDR5 effective)
Video Drivers NVIDIA GeForce 332.21 WHQL
Desktop Resolution 1920 x 1080
OS Windows 7 x64

Thanks to G.Skill for the RipjawsX 32GB DDR3 DRAM kit

The Math of Marketing: Not All 19nm NAND Is the Same
Comments Locked


View All Comments

  • nick2crete - Thursday, April 10, 2014 - link

    Christian ,
    the Crucial M550 has the Marvell 9189 controller ,so what are the differences from 9187,9188 and 9189
  • Kristian Vättö - Friday, April 11, 2014 - link

    9189 is an updated version of the 9187 with full DevSleep and LPDDR support.

    9188 is a light version of the 9187 with four channels instead of eight.
  • nick2crete - Friday, April 11, 2014 - link

    Thank you !

    maybe you should correct it in the review ,because as it is written is meant that the M550 has the 9187 or you meant the M500 probably ..
  • HisDivineOrder - Thursday, April 10, 2014 - link

    The main reason to release a derivative product is because "the other guys" are releasing new products and you don't want to seem behind.

    AKA AMD re-releasing the 7xxx series as R9 parts with new branding and new "newness." nVidia, Intel, they all do it. In fact, Intel's about to do it again.
  • payton2037 - Sunday, April 13, 2014 - link

    Start a Second Income™with the company that's first with Internet entrepreneurs!
    For more Details Please visit at :--
  • watersb - Monday, April 14, 2014 - link

    Fantastic overview of NAND drive internals. Bundle this up as an Amazon Single for $1.99 and take my money.
  • AbRASiON - Wednesday, April 16, 2014 - link

    Would I be right in assuming when the author writes "manufacturers are preparing for the PCI-e era" regarding SSD storage, we're looking at that NGFF or whatever it is, next gen mSATA port? I mean surely they don't expect us to blow a PCI-e port on storage? (I would if it was worth it, most wouldn't)
  • Antronman - Monday, April 21, 2014 - link

    PCIe storage already exists at the consumer level...
    Extremely expensive, 1.4TB Read 700MB Write PCIe SSDs.
    420GB, 1500USD.
  • Ultraspark - Thursday, April 24, 2014 - link

    On Amazon Plextor m5p 128gb cost about 117$, and not 200$. I wonder how did you found such price. Or on newegg prices are updated once per 2 year, or this is an cheap review "paid" by someone to put Plextor in a bad light. It is well known that the controller+memory tandem is a half job. The firmware do the other half of job. You'll never feel in real life few tens of Mbps or few thousands of IOPS. The main goal of plextor is reliability! Just remember the Sandforce devices with shitty firmware who die like no one else. The MxS series is a preparation for MxP series. Remember the new revision of M5S. It is almost M5P with very small difference, without a chance to feel that difference in real life. Just different firmware and case. So, let's be honest dear reviwer: a good car is just a half job. If you want to win you need a good driver. The same is with plextor. This is 1st firmware. It is just to work. The future firmwares will do the magic, like on M5 Series. And When you search for price, be honest to search for lowest, not for highest. Please correct from 200$ to 117$
  • Ultraspark - Thursday, April 24, 2014 - link

    Or change the supplier. I never buy from newegg.

Log in

Don't have an account? Sign up now