Crucial M550 128GB SSD Review

Crucial's M550 addresses issues that plagued the M500, such as performance. Read on as Chris tells us all about the new 128GB SSD model.

Published   |   Updated Tue, Nov 3 2020 7:00 PM CST
Manufacturer: Crucial
12 minute read time

Introduction & Specifications, Pricing, and Availability

Crucial M550 128GB SSD Review 01

We published a review of the Crucial M550 1TB already today, and we'll fill in the gaps tomorrow. In this review, we're focusing on the smallest capacity size in the M550 series, the 128GB. When Crucial released the M500, the big attraction was the new 20nm 128Gb NAND flash that allowed the company to manufacture large capacity SSDs at reasonable price levels. By doubling the capacity of the die, it took fewer die per SSD to reach the capacity points.

For larger SSDs, the strategy worked out great, but smaller capacity drives suffered performance issues due to parallelism, the number of die read and written to at the same time. The Crucial M550 128GB and 256GB drives still use 20nm flash but move back to 64Gb die sizes. This increases performance by allowing the controller to read and write to more flash at the same time.

Crucial now has a two-drive strategy for the SSD market. The M550 does not replace the M500; it compliments it. In our previous review, we learned that the 1TB M550 performed faster than the 960GB M500 but used more power at the same time. Offering a choice between value and performance opens the door for higher sales and gives power users a new choice when it comes to high performance SSDs.

Specifications, Pricing, and Availability

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Crucial's bringing the M550 to market in three form factors, 2.5-inch SATA, mSATA, and M.2 SATA. The new model uses the faster Marvell 88SS9189 controller, an upgrade over the 88SS9187 used on the M500. Three capacity sizes dominate the product range, 128GB, 256GB, and 512GB. The 1TB model is an exclusive 2.5-inch form factor model.

Crucial rates the M550 128GB at 550 MB/s sequential read with 90k random read, and 350 MB/s sequential write with 75k random writes. With SSD performance up to 20 times faster than spinners, it's hard to squabble over performance at this level, but the M550 numbers represent enthusiast class performance.

The 128GB capacity class is interesting when it comes to performance. Some manufactures moved to 20nm 128GB die, some are on 20nm asynchronous die, and others are using 64Gb die from Flash Forward. The best performance comes from 64Gb synchronous or Toggle die, but most manufacturers don't advertise the flash used. To be honest, some manufacturers change the flash without changing the model number or product SKU, something that happened with a major manufacturer this year. With Crucial, you don't have to worry about that because they are part of a fab company; they make the flash through subsidiary Micron. Moving forward, this will become a larger issue as controller innovation slows and flash lithography advances.

Crucial supports AES 256-bit hardware encryption that meets TCG Opal 2.0 and IEEE-1667 standards. Microsoft's eDrive is supported as long as your other hardware also supports the standard. M550 supports DEVSEP also and even offers host power loss protection.

At the time of writing, the Crucial M550 wasn't listed at e-tail shops, but the M550 will be ready for consumption by the time you read this. Crucial did send over MSRPs for the 2.5-inch models. The 128GB SKU we're looking at today should list for around $99.99. The 1TB model will list at $530.99, 512GB at $336.99, and 256GB at $168.99, all per Crucial's MSRP for a drive only kit.

Crucial M550 128GB SSD

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We're breezing through some of the product images today since the M550 is a 'drive only' kit. It does includes a 7mm to 9.5mm adapter bracket.

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Here we see the actual drive. Crucial has always swapped the label sides. The shiny sticker is on the bottom of the drive, and the information sticker is on what we associate with the top. Inside the case, the drive is also flipped around. This allows Crucial to put the controller facing the case side with more mass. This aids in cooling the controller and the DRAM next to the controller.

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As mentioned, Crucial includes a bracket that gives the 7mm drive full 9.5mm height. This is used in some drive cages designed for 9.5mm z-height and some notebook drive cages. The 7mm standard is commonly found in Ultrabook designs where 9.5mm drives will not fit.

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Inside, we found a Marvell controller, a single Micron DRAM package to cache table data, and sixteen NAND flash packages, eight on each side.

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The Marvell 88SS9189 is a faster version of the 88SS9187 used in the M500.

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Crucial used Micron 20nm flash.

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Crucial also used Micron DRAM. In this image, you can also see a bank of capacitors used for host power fail protection. This allows the data passing through the controller to write to the flash in a power fail event.

Benchmarks - 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

ATTO is a timeless benchmark used to provide manufacturers with data used to market storage products.

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Our early testing shows the M550 128GB achieving the sequential performance claims from Crucial. We achieved over 561 MB/s sequential read and nearly 370 MB/s sequential write. This is a good start for the M550.

Benchmarks - Sequential Performance

HD Tune Pro

Version and / or Patch Used: 4.00

Developer Homepage:

Product Homepage:

HD Tune is a Hard Disk utility which has the following functions:

Benchmark: measures the performance

Info: shows detailed information

Health: checks the health status by using SMART

Error Scan: scans the surface for errors

Temperature display

HD Tune Pro gives us accurate read, write, and access time results and, for the last couple of years, has gained popularity amongst reviewers. It is now considered a must-have application for storage device testing.

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Sequential performance on the M500 was never an issue, so we don't expect to have issues in this area with the M550. One issue we will have today is with other drives on the chart. The ADATA SX900 moved to 20nm flash since we tested it, and the Kingston V300 moved to 20nm asynchronous flash, so you shouldn't reference it to the V300 available at e-tailers today. The Intel 520 and OCZ Vector were discontinued.

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When comparing the M500 to the M550, the write performance in both sequential and random should show very large differences. Here we see the M500 averaging just 115.9 MB/s in HD Tune Pro sequential write, and the new M550 averages over 317 MB/s. This is a massive performance increase for the 128GB drive and makes it competitive with the fastest 128GB capacity class drives available on the market today.

HD Tach - Sequential Write Performance after Random Writes

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After hitting the M550 128GB with random writes, we retested sequential performance, this time at 128 KB. The drive dips to very low write performance levels, not much higher than 15 MB/s on the low-end. Later in this review, we'll show that this is partially due to aggressive background garbage collection similar to what Plextor uses and partially due to the foreground garbage collection taking place prior to a write event.

Benchmarks - AIDA64 Random Access Time

AIDA64 Random Access Time

Version and / or Patch Used: 1.60

Developer Homepage:

Product Homepage:

AIDA64 offers several different benchmarks for testing and optimizing your system or network. The Random Access test is one of very few, if not the only, that will measure hard drives' random access times in hundredths of milliseconds as oppose to tens of milliseconds.

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The read latency is steady and very low compared to mechanical HDDs.

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Write latency is also very low compared to mechanical HDDs but higher than some of the other SSDs. This can become an issue when working the drive hard or in RAID arrays where you want consistent latency.

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.

The software is used 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 Crucial M550 works with both compressible and incompressible data the same way, so performance stays the same regardless of data type.

Read IOPS through Queue Depth Scale

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Low queue depth 4k read performance is very close to other leading drives in this capacity size. The M550 128GB delivers nearly 9k IOPS at QD1 and scales all the way to 98k at QD32.

Scaling Write IOPS through Queue Scale

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We're very impressed with the 4k write IOPS on the M550. At QD1, the drive delivers just over 37k IOPS and scales all the way to 70k at QD32.

Benchmarks - CrystalDiskMark


Version and / or Patch Used: 3.0 Technical Preview

Developer Homepage:

Product Homepage:

Download here:

CrystalDiskMark is a disk benchmark software that allows us to benchmark 4k and 4k queue depths with accuracy.

Key Features:-

* Sequential reads/writes

* Random 4KB/512KB reads/writes

* Text copy

* Change dialog design

* internationalization (i18n)

Note: Crystal Disk Mark 3.0 Technical Preview was used for these tests since it offers the ability to measure native command queuing at 4 and 32.

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The M550 128GB reads data at various points at the same levels of other top-tier drives on the market.

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For the last year, we've praised SSDs that manage to best 150 MB/s in 4k QD1 write performance. It's a small club, but the Crucial M550 128GB made it in.

Benchmarks - PCMark Vantage Hard Disk Tests

PCMark Vantage - Hard Disk Tests

Version and / or Patch Used: 1.0.0

Developer Homepage:

Product Homepage:

Buy It Here

PCMark Vantage is the first objective hardware performance benchmark for PCs running 32-bit and 64-bit versions of Microsoft Windows Vista. PCMark Vantage is perfectly suited for benchmarking any type of Microsoft Windows Vista PC from multimedia home entertainment systems and laptops to dedicated workstations and high-end gaming rigs. Regardless of whether the benchmarker is an artist or an IT Professional, PCMark Vantage shows the user where their system soars or falls flat and how to get the most performance possible out of their hardware. PCMark Vantage is easy enough for even the most casual enthusiast to use yet supports in-depth, professional industry grade testing.

Futuremark has developed a good set of hard disk tests for their PCMark Vantage Suite. Windows users can count on Vantage to show them how a drive will perform in normal day-to-day usage scenarios. For most users, these are the tests that matter since many of the old hat ways to measure performance have become ineffective to measure true Windows performance.

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The Crucial M550 is at the top or in the top three of the highest performing drives in this capacity size in nearly all of the real-world tests in Vantage.

Benchmarks - PCMark Vantage - Drives with Data Testing

PCMark Vantage - Drives with Data Testing

For a complete breakdown on the Drives with Data Testing, please read this article. You will be able to perform this test at home with the files provided in the article; full instructions are included.

- Brief Methodology

SSDs perform differently when used for a period of time and when data is already present on the drive. The purpose of the Drives with Data testing is to show how a drive performs in these 'dirty' states. SSDs also need time to recover, either with TRIM or onboard garbage collection methods.

Drives with Data Testing - 25%, 50%, 75% Full States and Dirty / Empty Test

Files needed for 60 (64GB), 120 (128GB), 240 (256GB)

60GB Fill - 15GB, 30GB, 45GB

120GB Fill - 30GB, 60GB, 90GB

240GB Fill - 60GB, 120GB, 160GB

Empty but Dirty - a test run just after the fill tests and shows if a drive needs time to recover or if performance is instantly restored.

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With data on the drive, the M550 provides the highest level of performance when compared against the 128GB class drives that you can still purchase new today. This is an important metric that's rarely discussed.

Benchmarks - PCMark 8 2.0 Advanced Tests

Benchmarks - PCMark 2.0 Advanced Tests

Version and / or Patch Used: 2.0

Developer Homepage:

Product Homepage:

Buy It Here

Note: PCMark 8 Storage benchmark is ideal for testing the performance of SSDs, HDDs, and hybrid drives. Using traces recorded from Adobe Creative Suite, Microsoft Office, and a selection of popular games, PCMark 8 Storage highlights real-world performance differences between storage devices.

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If you have yet to read about our new worst case / recovery test, please feel free to do so. We are oversimplifying a complicated test in this section.

The M550 architecture fairs very well in our new advanced test in other capacity sizes but not in the 128GB capacity size. The M550, even if much better than the M500, still runs behind many of the other 128GB class drives in all three markers.

Benchmarks - DiskBench

DiskBench - Directory Copy

Version and / or Patch Used:

Developer Homepage: Nodesoft

Product Homepage: DiskBench

Download here:

Note: In this test, we use the Lenovo W530 Mobile Workstation and a SuperSpeed S301 SLC 128GB SSD to move a 15GB block of data to and from the target drive. This is part of our real-world test regiment. Roughly 45GB of data resides on the target drive before the '15GB Block' is transferred. The 15GB Block is the same data we built for the Data on Disk Testing and is a mix of compressible and incompressible data.

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In a notebook, the power management states limit SSD performance. In this test, we transfer data to and from the target drive while staying within the constraints of the link management, a power limiting feature by the system.

Again, the M550 fairs very well in this test and still outpaces the M500 by a large margin in the write test.

Benchmarks - Power Testing & Final Thoughts

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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When we tested the 1TB class models, the M500 delivered significantly more battery life than the M550. In the 128GB class, the two Crucial drives are much closer together in the amount of battery life delivered.

Final Thoughts

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Today, we looked at the two extremes of the M550 product line, the large 1TB model and the small 128GB. With both drives, we found a significant performance improvement with the M550 over the M500. The price of the new M550 is aggressive for a product in the upper tier of a dual-tier product line. Crucial's ability to control the majority of the components and flash help to keep the cost down and keeps reliability high.

Since most of us on TweakTown reference performance over all else other than reliability, we'll start there. The 128GB M550 is quite a bit faster than the M500 and comes very close to the Extreme II, 840 Pro, 840 EVO, and Vector 150 / Vertex 460 territory. These are, without a doubt, the highest performing drives on the market, and M550 sits right at home with this group. All of these drives have strong and weak points.

In this capacity size, latency is the one area where we can point to and determine if a drive is good or great. Sadly, this is an area where the M550 doesn't shine; the write latency is just too high, and that hurts write performance and would hurt RAID in high performance computing. For general computing, though, the M550 is amazing as we observed in Vantage.

The price of the 128GB M550 is very good, lower than many of the other drives we listed above. The MSRP is $99.99, but Crucial is always aggressive on price. The M500 has an MSRP of $99.99, but Newegg has them at $74.99. The M500 240GB is down to just $119.99, and, at that price, it might be difficult to not double the capacity while accepting a slightly slower M500.

As we progress further in the SSD game, one thing is becoming clear. If you want to survive, you need a NAND flash fab. If you don't have a fab, then the deck is stacked against you. I think this is important for potential buyers to understand because we've already seen non-fab companies play with flash to keep the factories rolling.

Crucial is one of the few fab companies, so you don't have to worry about the drive you buy using different parts than the products reviewed. The supply of flash and DRAM will not dry up for Crucial. At the same time, Marvell will sell controllers to fab companies with flash ready to go before they do third parties trying to piece SSDs together with fewer chips in the game. For end users this means reliability and peace of mind.

Every drive has a trade off somewhere, but if you need one 128GB drive to do it all, this is it. The M550 is a solid product that does well everywhere.

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