Crucial MX100 256GB SSD Review

Crucial unleashes new 16nm MLC flash to combat Samsung's 3-bit MLC in price and performance. Read on and see what Chris thinks of the new MX100 256GB SSD.

Manufacturer: Crucial
13 minutes & read time

Introduction & Specifications, Pricing and Availability

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You may have caught our recent coverage of the PNY Optima scandal that led to a boycott of PNY and Kingston SSDs on Reddit. Several technology websites picked up the initial blog post and post inspection editorial. For the most part, the industry chimed in with supporting remarks, damning both companies for changing important components after reviews hit the web. There were a handful of dissenting opinions, though. All were based on fiction, like those buying low-cost SSDs don't care about performance, and the manufacturers can't keep up with the demand during manufacturing, so they get to just throw together any product they want and sell it under the same model name. The latter is what really caught my attention and the new Crucial MX100 proves the claim false.

Crucial is part of the Micron and Lexar, Micron being one of the largest NAND flash and DRAM manufacturers in the world. Crucial gets first pick of NAND flash made by Micron, in a cooperation with Intel called IMFT. Both Micron and Crucial have SSD product lines, Micron sells to OEM customers like Dell, and Crucial sells to the channel, customers like you and me. In a roundabout way, we can say that Crucial has NAND flash production via proxy, just like Intel, Samsung, SanDisk, Toshiba and SK Hynix.

As the SSD market grows, these NAND flash manufacturers will make sure they have NAND flash for themselves before selling flash to third-party SSD manufacturers, those without NAND flash product capability. SSD prices are rapidly shrinking and so are profit margins per unit sold. When you have NAND flash production, it's really not a big deal, but when you have to buy flash and sell a drive at a competitive price point, it certainly is.

What we're seeing now is the lower-end of the totem pole cutting corners to stay competitive with the six NAND flash manufacturers. If they were having problems before, then things are about to get a whole lot worse.

Specifications, Pricing and Availability

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Hot on the heels of Crucial's flagship M550 release is the replacement for M500, the MX100. Crucial positioned the MX100 at the lower tier of a two-tier structure - one product designed for the performance market, and the other designed for mainstream users. 'Mainstream users' is really an odd term, but it means those who don't want to spend a lot of money on a product.

Nearly all SSDs deliver enthusiast levels of performance, but some perform a bit better under heavy workloads. A true mainstream user wouldn't be able to tell the difference between an expensive SSD and one that costs less than $100. It's a significant price point though because it's an easy to swallow amount, even if you only care about your PC booting quicker and web pages loading faster.

The Crucial MX100 ships in three capacity sizes - 128GB, 256GB and 512GB. All three capacity sizes read sequential data at 550 MB/s, but the sequential write speeds vary by the capacity and range from 150 MB/s for the 128GB model to an impressive 500 MB/s on the 512GB model.

We recorded the current prices at the time of writing and snagged a screenshot from Newegg, shown at the top of this page. The MX100 128GB comes in at just $77.99, the 256GB model costs just $109.99 and the 512GB model just $214.99. It seems Newegg is even reducing the cost of shipping on the MX100, just 99 cents.

Things get interesting on the technology side. While the 128GB MX100 uses 128Gb die capacity 20nm NAND flash, like the larger capacity M550 series, the 256GB and 512GB MX100 models use new 16nm flash. Micron is able to produce more 16nm die per wafer than 20nm die. Since the wafer price is the same, Micron gets more parts per wafer at 16nm, which trickles down to mean lower price SSDs. 16nm lithography is Micron's answer to Samsung's 3-bit MLC (Triple-Level Cell, TLC) flash. For years, we've heard that price is the leading reason for users to pass on solid state storage technology, and Micron / Crucial's 16nm flash addresses the price issues.

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You may think the MX100 also cuts technology features from the flagship M550, but that isn't the case. The MX100 checks all of the boxes with an extensive list of features. Those include hardware encryption via TCG Opal 2.0 and Microsoft's eDrive. Crucial's RAID technology is also included, as well as adaptive thermal protection, power loss protection and a host of industry standards.

The MX100 series of products carry a three-year warranty with a TBW of 72TB or 40GB per day. To frame the writes per day, I've used the same SSD in my daily use notebook, the one that I take everywhere, and average 23GB writes per day.

PRICING: You can find the Crucial MX100 256GB 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 Crucial MX100 256GB SSD retails for $109.99 at Amazon.

Canada: The Crucial MX100 256GB SSD retails for CDN$160.45 at Amazon Canada.

Crucial MX100 256GB SSD

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The MX100 ships in a full color retail package.

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Inside the package we found a paper manual with instructions on how to download Acronis True Image HD (and the activation key), the SSD and a 7mm to 9.5mm adapter shim.

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The MX100 case is the same used on Crucial's M550 flagship model and doubles as a heat sink for the Marvell controller, DRAM and NAND flash.

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The MX100 is a 7mm design so the drive will fit in a growing number of Ultrabook designs that are too thin for a full height 9.5mm SSD. Crucial does ship a black plastic shim that increases the drive height to the standard 9.5mm and required for some drive sleds.

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To increase performance, Crucial used sixteen NAND flash packages.

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Paired with the Micron 16nm flash is a Marvell controller, the same used on the flagship M550.

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It's safe to say that Samsung's new V-NAND is the most advanced flash on the market now with its vertical structure, but Micron getting to 16nm lithography is also impressive.

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This model also includes power loss protection.

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Test System Setup and ATTO Baseline Performance

Desktop Test System

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Lenovo W530 - Mobile Workstation

We use two systems for SSD testing. The desktop runs a majority of the tests, and the Lenovo W530 runs the notebook power tests as well as the real-world file transfer benchmark.

ATTO - Baseline Performance

Version and / or Patch Used: 2.34

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Using ATTO to get a baseline for performance, we see the MX100 240GB delivers just over 556 MB/s sequential read and 346 MB/s sequential write performance.

Benchmarks - Sequential Performance

HD Tune Pro - Sequential Performance

Version and / or Patch Used: 4.55

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We recently revamped out charts, after this review the MX100 will replace the M500 in all of our capacity size charts. We recorded the MX100 256GB at 453.1 MB/s sequential read speeds while reading across the entire LBA range. Most modern SSDs score very well when reading sequential data though, as the chart shows.

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Scoring well when writing sequential data is another story. The Crucial MX100 scored just over 300 MB/s when writing sequential data across the LBA range. This is a 100 MB/s improvement over the M500 in the same test, but 27 MB/s slower than Crucial's M550.

HD Tach - Sequential Write Performance after Random Writes

Version and / or Patch Used:

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After a reasonable number of random reads and writes, we ran HD Tach to view any issues with write performance fall off. The MX100 256GB does well in a majority of the tests, but towards the end, very clearly we see where the dirty flash is.

Benchmarks - Anvil Storage Utilities

Anvil Storage Utilities

Version and / or Patch Used: RC6

So what is Anvil Storage Utilities? First of all, it's 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 on several international forums, has been updating the software steadily 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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Compressible and incompressible write performance is the same on the MX100, so you won't notice a slowdown when working with pictures, audio, and other highly compressed files.

Low Queue Depth Read IOPS

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We made a change on this page and divided the low queue depth performance from the high queue depth performance. Consumers should focus mainly on low queue depths, even though manufactures advertise high queue depth performance. The QD1 IOPS rating has a red highlight around it since it's one of the most important metrics to look at.

The MX100 256GB delivers nearly 8,200 random read IOPS at QD1. The drive scales well from there, doubling at QD2 and nearly doubling again at QD4.

High Queue Depth Read IOPS

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It's rare for consumers to reach the high queue depths shown in this chart, but with heavy multitasking and intense tasks, like booting the system, they are possible. The MX100 nearly hit 100K IOPS in our QD32 read test.

Low Queue Depth Write IOPS

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It's easier to reach higher queue depths when writing data while multitasking.

High Queue Depth Write IOPS

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The Crucial MX100 256GB achieves nearly 80K random IOPS at QD4 and then everything levels off in this chart, but we don't see the performance shrink as the load increase.

Benchmarks - 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 until we get to 100% writes, in 10% increments. We believe this will be the next major area SSD manufacturers will address after performance consistency.

Mixed Workload Bandwidth

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This is the debut for this benchmark on the pages of TweakTown, at least for the consumer SSD reviews anyway. What we see is a bathtub curve as the drives work through mixed workloads. Mixed workloads means reads and writes at the same time. We first started looking at this a few months back when we noticed some odd behavior on the Samsung XP941 (a PCIe 2.0 x4 OEM SSD). PCIe SSDs should be full-duplex, they can read and write at the same time. SATA drives are only half-duplex, they can read and write, but not at the same time.

As you can see here, the two M.2 PCIe SSDs have problems reading and writing at the same time. After we get more results, we'll pull the PCIe M.2 drives from this chart and replace them with more SATA drives. The results also show one of the hidden reasons why LSI SandForce drives (like the Intel Pro 2500 shown here with 50% entropy) always feel much faster than what most benchmarks lead us to believe.

Our focus today though is the Crucial MX100 256GB. The drive starts doing very well with 100% read but as soon as we add 10% writes, the performance drops to less than 200 MB/s. The performance never recovers to complete the bathtub curve because we're testing in steady state.

80% Read / 20% Write Bandwidth

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We found that the 80/20 mix is a good measuring point for consumers. 70/30 for prosumer environments. In this chart we plot the 80/20 mix with the 256GB class drives we've tested to date. The Crucial MX100 is the least desirable, but it's also the only mainstream price class drive in the chart. We'll expand this data in the coming weeks.

Mixed Workload Response Time

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Here we see the latency results from the same tests under the same conditions. This is measured in milliseconds and shows the average time from multiple runs at each mix.

PCMark 8 Consistency Test

Futuremark PCMark 8 Extended - Consistency Test

Version and / or Patch Used: 2.0.228

Heavy Usage Model:

FutureMark's PCMark 8 allows us to wear the test drive down to a reasonable consumer steady state and then watch the drive recover on its own through garbage collection. To do that, the drive gets pushed down to steady state with random writes and then idle time between a number of tests allows the drive to recover.

Precondition Phase:

1. Write to the drive sequentially through up to the reported capacity with random data.

2. Write the drive through a second time (to take care of overprovisioning).

Degradation Phase:

1. Run writes of random size between 8*512 and 2048*512 bytes on random offsets for 10 minutes.

2. Run performance test (one pass only).

3. Repeat 1 and 2 for 8 times, and on each pass increase the duration of random writes by 5 minutes.

Steady state Phase:

1. Run writes of random size between 8*512 and 2048*512 bytes on random offsets for 50 minutes.

2. Run performance test (one pass only).

3. Repeat 1 and 2 for 5 times.

Recovery Phase:

1. Idle for 5 minutes.

2. Run performance test (one pass only).

3. Repeat 1 and 2 for 5 times.

Storage Bandwidth

PCMark 8's Consistency test provides a ton of data output that we use to judge a drive's performance. Here we see the three states of performance for the select SSDs, light use, consumer steady state and worst case.

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On this chart, we have a handful of other mainstream SSDs currently on the market - Corsair's Force LX, Transcend's SSD 340, Plextor's M6S, SanDisk's Ultra Plus and PNY's Optima (Silicon Motion version). The MX100 does well here under light use, but performance drops off rapidly as the drive moves into consumer steady state.

Storage Bandwidth All Tests

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Here we see all of the test stages as the drives start out in worst-case conditions and performance comes back through internal garbage collection and idle time. The MX100 is the orange line on the chart (click to enlarge) and does reasonable well for a low-cost SSD.

PCMark 8 Consistency Test - Continued

Total Access Time

The access time test measures the total latency across all 18 tests. This is one of, if not the most important test we run at this time for consumer SSDs. When your latency is low your computer feels fast, it's just that simple.

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Low-cost SSDs will never be performance leaders, several of which we have on this chart. It's easy to spot the group of mainstream SSDs on the chart, as they are all grouped together in latency performance, minus the Transcend SSD 340 that shipped with immature firmware and the SanDisk Ultra Plus 256GB that outperforms the group. The PNY Optima does a bit better than the Ultra Plus, but if you buy one, you never know what controller it will ship with.

Disk Busy Time

In the final test, we measure the amount of time the drive worked to read and write the data to complete the test. When a drive is active, it uses more power so the faster it can complete the tasks the faster it can fall into a low power state.

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Here we see the disk busy time, the amount of time the drive needs to work to complete a task, through the tests. This can affect battery life in notebooks if the drive has to work harder for longer amounts of time. The faster a drive can complete a task, the faster it can drop back down into a lower power state.

Benchmarks - Power Testing

Bapco MobileMark 2012 1.5

Version and / or Patch Used: 2012 1.5

Developer Homepage:

Test Homepage:

MobileMark 2012 1.5 is an application-based benchmark that reflects usage patterns of business users in the areas of office productivity, media creation and media consumption. Unlike benchmarks that only measure battery life, MobileMark 2012 measures battery life and performance simultaneously, showing how well a system design addresses the inherent tradeoffs between performance and power management.

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A reader suggested we replace our graph with a chart that shows the time the system ran before running out of power. We accepted and also expanded with the chart below that shows performance while limited by power.

The Lenovo W530 paired with the Crucial MX100 256GB delivered 261 minutes of battery life.

Power Limited Performance

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MobileMark runs a series of real-world software while slowly ticking off minutes until the battery finally depletes. The test also measures performance. In order to deliver more battery life, notebooks reduce processor, PCIe, SATA and DRAM speed until an intensive task asks for more performance.

As you can see, under these limiting conditions, most SSDs perform the same, but some drives do a bit better than others while under battery power.

Final Thoughts

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The Crucial MX100 256GB isn't going to win any awards based on performance alone, but this drive brings more to the table than just raw speed. Compared to a mechanical disk drive, the MX100 is significantly faster and for its target market, that's what is important, as well as the price. The 256GB model we tested today costs just $109.99, a reasonable amount for this level of performance.

I chose the image above of a statement I found on Crucial's website. There are several low-cost SSDs on the market now, and the $90 to $120 price point for 256GB drives is starting to fill with products. Over the last six months, we've noticed a few 'issues' that we really don't like and we certainly don't endorse.

One thing we like about Crucial is the fact that the company doesn't need to play loose with the build of materials. The drive you purchase is the same drive we tested here today, period. Over time, Crucial will update the firmware to increase performance and fix any corner case issues, but for the most part, when you buy a MX100, you will get a Marvell controller paired with Micron 16nm ONFi NAND flash.

Before the drive hit the market and before any firmware changes become available, the drives are thoroughly tested. As profit margins shrink for SSDs, some companies may choose to do anything they can to stay competitive in this market. Crucial is one of the few companies that will not bend on principal, and you can trust the quality of the components they use.

For what it is, the Crucial MX100 is a very good SSD. It's not the best performing low-cost SSD on the market, but it's one of the few solid products that we can endorse because of the high quality. Propping up the MX100 is a long list of advanced features and a decent three-year warranty.

PRICING: You can find the Crucial MX100 256GB 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 Crucial MX100 256GB SSD retails for $109.99 at Amazon.

Canada: The Crucial MX100 256GB SSD retails for CDN$160.45 at Amazon Canada.

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