Home Helpful Hints Connector m 2. Install the SSD m2 drive into the computer motherboard. Which connectors use M.2 drives

Helpful Hints

Connector m 2. Install the SSD m2 drive into the computer motherboard. Which connectors use M.2 drives

Become more and more popular due to the numerous benefits. They are tiny and do not take up much space in a laptop, mini-PC or desktop computer case (they are installed directly on the motherboard), but at the same time, they allow you to achieve speeds that are not available with "regular" 2.5-inch SSDs.

You need to know that M.2 SSD drives are available in various formats (they can vary in length), as well as two main variations - using the SATA interface (cheaper and slower) and using the PCI Express / NVMe interface (more expensive and faster). The currently used SATA interface allows for a maximum throughput of 6 Gb/s, while PCIe x4 up to 32 Gb/s, so the performance difference can be very large, as is the price.

By the way, it is worth mentioning Intel Optane memory (not to be confused with Intel Optane SSD), which has the M.2 media format, but serves to speed up the operation of HDD drives. This technology only works on the newer Intel platforms, but it works surprisingly well, allowing for a significant increase in the speed of magnetic disks.

M.2 connectors on motherboards can support both, or only one - it's worth checking before buying so you don't try to install a PCIe/NVMe drive in a SATA-only M.2 connector, for example. It is worth noting that you can also connect M.2 PCIe drives in the U.2 port (via an adapter), and in the PCI Express slot.

Below are presented as most efficient SSD designs, which use the PCI Express x4 3.0 (NVMe) bus, as well as cheaper / less powerful models that use the SATA standard.

Inexpensive M.2 SSD

Among cheap M.2 drives, how can you find designs that use SATA and PCIe. The capabilities of the former are close to 2.5-inch SSDs, but the size speaks in their favor, as well as the fact that some computers may not serve M.2 NVMe drives.

WD Green PC SSD G2 (120 GB)

The WD Green PC SSD G2 series is one of the cheaper M.2 options. Based on the SATA interface, the 120 GB model achieves 545 MB/s read and 430 MB/s write performance. The manufacturer used a 4-channel Silicon Motion SM2246XT controller and Toshiba 3D TLC NAND memory cells (but without cache memory) here.

Main characteristics:

Disc Format: M.2 2280
Capacity: 120 GB
Disk interface: SATA III
Write speed: 430MB/s
Read speed: 545MB/s
Memory cells: Toshiba 3D TLC NAND

ADATA XPG SX6000 (128 GB)

The ADATA XPG SX6000 is, in turn, one of the cheapest M.2 SSD media using PCIe 3.0 x2. The manufacturer used a Realtek RTS5760 4-channel controller and modern 3D TLC NAND memory here. Claimed speeds reach 730/660 MB/s. A warranty of up to 5 years is provided, but it is limited by the TBW factor (75 TB of data written).

It is worth noting that the 256 GB and 512 GB models are not only affordable, but also much faster (1000/800 MB/s).

Main characteristics:

Disc Format: M.2
Capacity: 128 GB
Interface: PCI-Express 3.0 x2 (NVMe), PCIe 3.0 x2/NVMe 1.2
Write speed: 660MB/s
Read speed: 730MB/s

ADATA Ultimate SU800 M.2 (250 GB)

ADATA Ultimate SU800 M.2 drives are very good value for money. Modern 3D TLC Nand memory cells and a 4-channel Silicon Motion SM2258 controller are used.

It's a SATA drive, so performance is identical to the 2.5-inch version, with read speeds up to 560MB/s and write speeds up to 520MB/s. A 3-year warranty is provided, but is not limited by the TBW factor. Along with the disc, we receive the Acronis True Image HD software package.

Main characteristics:

Capacity: 256 GB
Interface: SATA III M.2
Write speed: 520MB/s
Read speed: 560MB/s
Memory cells: Micron 3D TLC NAND

M.2 SSD for laptop

In the case of laptops, this will often be the only drive in the computer, so it is worth taking care of sufficient capacity - do not invest in an SSD with a capacity below 240/256 GB. We should also pay attention to the type of interface - whether the media supports the SATA or PCIe interface, and which format (longer, 2280, or shorter, 2260 or 2242).

Crucial MX500 M.2 (250 GB)

Crucial's latest generation of SATA SSDs, the MX500 is another successful hit in the mid-range performance segment. The M.2 version of the drive performs quite well, with claimed speeds reaching 560 MB/s for reading and 510 MB/s for writing data. Crucial provides a 5 year warranty (limited to 100 TB TBW).

Main characteristics:

Disc Format: M.2 2280
Capacity: 250 GB
Interface: SATA III
Write speed: 510MB/s
Read speed: 560MB/s
Memory cells: Micron 3D TLC NAND

Transcend MTS420 (240 GB)

Transcend MTS420 in 240GB version is a very good suggestion for users who need small format 2242 M.2 media. The manufacturer has listed maximum speeds of 560 MB/s read and 500 MB/s write. It is worth noting that many other discs in this format are characterized by worse characteristics. The manufacturer gives a 3-year warranty on it.

Main characteristics:

Disc format: M.2 2242
Capacity: 240 GB
Interface: SATA III
Write speed: 500MB/s
Read speed: 560MB/s
Memory cells: Micron 3D TLC NAND

ADATA XPG SX8200 (480 GB)

This is a good suggestion for laptop users who can install M.2 2280 PCIe format SSD media in their machine. If the laptop boasts an M.2 PCIe 3.0 x4 connector, the speeds will be 3200 MB / s when reading and 1700 MB / s when writing. The XPG SX8200 drive is covered by a 5-year manufacturer's warranty.

Main characteristics:

Disc Format: M.2 2280
Capacity: 480 GB
Write speed: 1700MB/s
Read speed: 3200MB/s
Memory cells: Micron 3D TLC NAND

Best M.2 SSDs

Best M.2 Drives have amazing performance, and their efficiency is close to the limit of the PCI Express interface (the best of the drives presented here reaches the maximum speed 3.5 GB per second). Obviously, this is reflected in the high price. Such discs can be recommended to professionals, for example, those who work with complex video projects in 4K resolution.

GOODRAM IRDM Ultimate (480 GB)

IRDM Ultimate 480 GB is a good offer for more demanding users. Importantly, the kit includes an adapter for a PCI Express slot. The manufacturer also installed a heat sink that protects the drive from overheating. Onboard is an 8-channel Phison PS5007-E7 controller and durable Toshiba A19 MLC NAND memory cells. Maximum speeds reach 2900/2200 MB/s. The IRDM Ultimate series is covered by a 5-year manufacturer's warranty with no data write limitation.

Main characteristics:

Disc Format: M.2 2280 / AiC HHHL
Capacity: 480 GB
Interface: PCIe 3.0 x4/NVMe 1.2
Write speed: 2200MB/s
Read speed: 2900MB/s
Memory cells:Toshiba A19 MLC NAND

Intel SSD 760p (512 GB)

The Intel SSD 760p is an efficient SSD for desktops and modern laptops using the M.2 connector and PCIe 3.0 x4 interface. On board is a Silicon Motion SM2262 controller and IMFT 3D TLC NAND memory cells. The maximum speeds are 3230 MB/s for reading and 1625 MB/s for writing. The manufacturer provides a 5-year warranty for drives, but limited to TBW (288 TB of recording).

Main characteristics:

Disc Format: M.2
Capacity: 512 GB
Interface: PCI-Express 3.0 x4 (NVMe)
Write speed: 1625MB/s
Read speed: 3230MB/s
Memory cells: IMFT 3D TLC NAND

Samsung SSD 970 EVO (500 GB)

The SSD 970 EVO is Samsung's third generation of high-speed M.2 PCIe storage media. The 970 EVO models are designed for users who are looking for very fast, but not top-of-the-line solutions - this is the combination we will find in the 970 PRO models. The declared read speed reaches 3400 MB / s, and writes - 2300 MB / s. The hard drives of the 970 EVO series are covered by a 5-year manufacturer's warranty - we recall that the warranty period in previous models of the 960 EVO was only 3 years.

Main characteristics:

Disc Format: M.2 2280
Capacity: 500 GB
Interface: PCIe 3.0 x4/NVMe 1.3
Write speed: 2300MB/s
Read speed: 3400MB/s
Memory cells: Samsung TLC V-NAND

Samsung SSD 970 PRO (1TB)

The Samsung 970 PRO 512GB is the absolute top storage M.2 PCIe SSD designed for professionals. The manufacturer used ultra-reliable MLC V-NAND memory here, so users can not be afraid for their data. It is difficult to squeeze even more out of the PCIe 3.0 x4 interface, so the media reaches speeds of 3500 MB / s in reading and 2300 MB / s in writing. The 970 PRO series hard drives are backed by a 5-year manufacturer's warranty.

Main characteristics:

Disc Format: M.2 2280
Capacity: 1000 GB
Interface: PCIe 3.0 x4/NVMe 1.3
Write speed: 2700MB/s
Read speed: 3500MB/s
Memory cells: Samsung MLC V-NAND

Both in the past and this year, articles about SSDs can be safely started with the same passage: “The solid-state drive market is on the verge of major changes.” For many months now, we have been looking forward to the moment when manufacturers finally start releasing fundamentally new models of mass SSDs for personal computers, which will use a faster PCI Express bus instead of the usual SATA 6 Gb / s interface. But the bright moment when the market is flooded with fresh and noticeably more high-performance solutions, everything is postponed and postponed, mainly due to delays in bringing the necessary controllers to mind. The same single models of consumer SSDs with a PCI Express bus, which nevertheless become available, are still clearly experimental in nature and cannot impress us with their speed.

Being in such a languid expectation of changes, it is easy to lose sight of other events that, although they do not have a fundamental impact on the entire industry, are nevertheless important and interesting. Something similar just happened to us: quietly in the consumer SSD market, new trends began to spread, to which we had hardly paid attention until now. SSDs of a new format - M.2 - began to appear on sale in large quantities. A couple of years ago, this form factor was discussed only as a promising standard, but over the past year and a half, it has managed to gain a huge number of supporters among both platform developers and SSD manufacturers. As a result, M.2 drives are not uncommon today, but an everyday reality. They are produced by many manufacturers, they are freely sold in stores and installed everywhere in computers. Moreover, the M.2 format has managed to win a place for itself not only in mobile systems, for which it was originally intended. Many desktop motherboards today are also equipped with an M.2 slot, as a result of which such SSDs are actively penetrating, including classic desktops.

With all this in mind, we have come to the conclusion that it is necessary to pay close attention to M.2 SSDs. Despite the fact that many models of such flash drives are analogues of the usual 2.5-inch SATA SSDs, which are tested by our laboratory on a regular basis, there are also original products among them that do not have twins of the classic form factor. Therefore, we decided to catch up and conduct a unified summary testing of the most popular capacities of 128 and 256 GB available in domestic stores M.2 SSD. Assistance in the implementation of this venture was provided to us by the Moscow company " Regard”, offering an extremely wide range of SSDs, including in the M.2 form factor.

⇡ Unity and Diversity of the World M.2

M.2 slots and cards (previously called Next Generation Form Factor - NGFF) were originally designed as a faster and more compact replacement for mSATA, a popular standard used by solid state drives in various mobile platforms. But unlike its predecessor, M.2 offers fundamentally more flexibility in both logical and mechanical terms. The new standard describes several options for the length and width of cards, and also allows you to use both SATA and faster PCI Express interfaces to connect solid state drives.

There is no doubt that PCI Express will replace the drive interfaces we are used to. The direct use of this bus without additional add-ons allows you to reduce latency when accessing data, and due to its scalability, it significantly increases throughput. Even two PCI Express 2.0 lanes can provide significantly higher data transfer rates compared to the usual SATA 6 Gb / s interface, and the M.2 standard allows you to connect to an SSD using up to four PCI Express 3.0 lanes. The foundation for bandwidth growth thus laid will lead to a new generation of high-speed SSDs capable of faster operating system and application loading, as well as lower latency when moving large amounts of data.

SSD interface	Maximum theoretical bandwidth	Maximum real throughput (estimate)
SATA III	6 Gb/s (750 MB/s)	600 MB/s
PCIe 2.0x2	8 Gbps (1 GB/s)	800 MB/s
PCIe 2.0 x4	16 Gbps (2 GB/s)	1.6 GB/s
PCIe 3.0 x4	32 Gbps (4 GB/s)	3.2 GB/s

Formally, the M.2 standard is a mobile version of the SATA Express protocol described in the SATA 3.2 specification. However, it so happened that over the past couple of years, M.2 has spread much more widely than SATA Express: M.2 connectors can now be found on current motherboards and laptops, and SSDs in the M.2 form factor are widely available for sale. SATA Express is not able to boast of such support from the industry. This is partly due to the greater flexibility of M.2: depending on the implementation, this interface can be compatible with devices using the SATA, PCI Express, and even USB 3.0 protocols. Moreover, in its maximum version, M.2 supports up to four PCI Express lines, while SATA Express connectors are capable of transmitting data over only two such lines. In other words, today it is M.2 slots that seem not only convenient, but also a more promising foundation for future SSDs. Not only are they suitable for both mobile and desktop applications, they also offer the highest throughput of any existing consumer SSD connectivity options.

However, given the fact that the key property of the M.2 standard is the variety of its types, it should be borne in mind that not all M.2 drives are the same, and their compatibility with various versions of the corresponding slots is a separate story. For starters, commercially available M.2 SSD boards are 22mm wide but come in five lengths: 30mm, 42mm, 60mm, 80mm or 110mm. This dimension is reflected in the marking, for example, the M.2 2280 form factor means that the drive card has a width of 22 mm and a length of 80 mm. For M.2 slots, on the other hand, a complete list of dimensions of drive cards with which they can be physically compatible is usually indicated.

The second feature that differentiates different M.2 variants is the "keys" in the slotted slot and, accordingly, in the knife slot of the cards, which prevent the installation of drive cards in slots that are logically incompatible with them. At the moment, M.2 SSD uses two options for the location of the keys from the eleven different positions described in the specification. Two more options have found use on WLAN and Bluetooth cards in the M.2 form factor (yes, this happens, for example, the Intel 7260NGW wireless adapter), and seven key positions are reserved for the future.

	M.2 slot with type B key (Socket 2)	M.2 slot with M key (Socket 3)
Scheme
Key location	Contacts 12-19	Contacts 59-66
Supported interfaces	PCIe x2 and SATA (optional)	PCIe x4 and SATA (optional)

M.2 slots can only have one partition key, but M.2 cards can have multiple notch keys at once, making them compatible with multiple slot types at the same time. The type B key, located instead of pins 12-19, means that no more than two PCI Express lanes are connected to the slot. The type M key, which occupies pin positions 59-66, means that the slot has four PCI Express lanes and therefore can provide higher performance. In other words, an M.2 card must not only be the right size, but also have a key layout that is compatible with the slot. At the same time, the keys not only limit the mechanical compatibility between various connectors and M.2 form factor boards, but also perform another function: their location prevents the drives from being installed incorrectly in the slot.

The information given in the table should help to correctly identify the type of slot available in the system. But you need to keep in mind that the possibility of mechanical docking of the slot and the connector is only a necessary, but not a sufficient condition for their full logical compatibility. The fact is that slots with keys B and M can be used not only for the PCI Express interface, but also for SATA, but the location of the keys does not provide any information about its absence or presence. The same goes for M.2 card slots.

	Knife connector type B	Knife connector type M	Knife connector with keys type B and M
Scheme
Slot location	Contacts 12-19	Contacts 59-66	Contacts 12-19 and 59-66
SSD interface	PCIe x2	PCIe x4	PCIe x2, PCIe x4 or SATA
Mechanical compatibility	M.2 slot with type B key	M.2 slot with M key	M.2 slots with Type B or Type M keys
Common SSD Models	Not	Samsung XP941 (PCIe x4)	Most M.2 SATA SSDs Plextor M6e (PCIe x2)

There is one more problem. It lies in the fact that many motherboard developers ignore the requirements of the specifications and install the most “cool” M-key slots on their products, but only two of the four PCIe lanes are placed on them. In addition, the M.2 slots available on motherboards may not be compatible with SATA drives at all. In particular, ASUS sins with its love for installing M.2 slots with reduced SATA functionality. SSD manufacturers adequately respond to these challenges, many of which prefer to make both key cutouts on their cards at once, which makes it possible to physically install drives in M.2 slots of any type.

As a result, it turns out that it is impossible to determine the real capabilities, compatibility, and availability of the SATA interface in M.2 slots and connectors by external signs alone. Therefore, full information about the features of the implementation of certain slots and drives can only be obtained from the passport characteristics of a particular device.

Fortunately, at the moment the range of M.2 drives is not so large, so the situation has not had time to get completely confused. In fact, there is only one PCIe x2 M.2 drive model on the market so far, the Plextor M6e, and one PCIe x4 model, the Samsung XP941. All other flash drives available in stores in the M.2 form factor use the familiar SATA 6 GB / s protocol. At the same time, all M.2 SSDs found in domestic stores have two key cutouts - in positions B and M. The only exception is Samsung XP941, which has only one key - in position M, but it is not sold in Russia.

However, if your computer or motherboard has an M.2 slot and you plan to populate it with an SSD, there are a few things you need to check first:

Does your system support M.2 SATA SSD, M.2 PCIe SSD, or both?
If the system has support for M.2 PCIe drives, how many PCI Express lanes are connected to the M.2 slot?
What key layout on the SSD card does the M.2 slot in the system allow?
What is the maximum length of an M.2 card that can be installed in your motherboard?

And only after you can definitely answer all these questions, you can proceed to the selection of a suitable SSD model.

Crucial M500

The Crucial M500 solid state drive in M.2 format is an analogue of the well-known 2.5-inch model of the same name. There are no architectural differences between a “large” flash drive and its M.2 counterpart, which means that we are dealing with low-cost SSDs based on the popular Marvell 88SS9187 controller and equipped with 20nm flash memory manufactured by Micron with 128-gigabit cores . To fit the drive on an M.2 card that measures only 22x80mm, a tighter layout and flash memory chips with denser packing of MLC NAND crystals were used. In other words, the Crucial M500 is hardly able to surprise anyone with its hardware design, everything in it is familiar and has long been familiar.

For tests, we received two models - with a capacity of 120 and 240 GB. As with 2.5-inch SSDs, their capacities were somewhat reduced relative to the usual multiples of 16 GB, which means there is a larger spare area, which in this case occupies 13 percent of the total flash memory array. The M.2 versions of the Crucial M500 look like this:

Crucial M500 120GB (CT120M500SSD4)

Crucial M500 240GB (CT120M500SSD4)

Both drives are 2280 format M.2 cards with type B and M keys, which means they can fit into any M.2 slot. However, do not forget that the Crucial M500 (in any version) is a drive with a SATA 6 Gb / s interface, so it will only work in those M.2 slots that support SATA SSDs.

Both modifications of the considered drive carry four flash memory chips. On a 120 GB drive, this is a Micron MT29F256G08CECABH6, and on a 240 GB drive, it is MT29F512G08CKCABH7. Both types of chips are assembled from 128-gigabit 20-nm MLC NAND crystals, respectively, in the 120-gigabyte version of the drive, the eight-channel controller has one flash memory device on each of its channels, and in the 240-gigabyte SSD it uses two-fold device interleaving. This explains the noticeable differences in the performance of the Crucial M500 of different volumes. But both considered modifications of the Crucial M500 are equipped with the same amount of RAM. Both SSDs have a 256 MB DDR3-1600 chip.

It should be noted that one of the positive properties of Crucial consumer drives is hardware data integrity protection in case of sudden power outages. M.2 modifications of the Crucial M500 also have this property: despite the size of the board, flash drives are equipped with a battery of capacitors that allow the controller to shut down normally and save the address translation table in non-volatile memory even in case of any excesses.

Crucial M550

Crucial was one of the first to embrace the new form factor, duplicating all of its consumer SSD models in both traditional 2.5-inch and M.2 formats. Not surprisingly, after the appearance of the M.2 versions of the M500, corresponding modifications of the newer and more powerful Crucial M550 model were released to the market. The general approach to designing such SSDs has been preserved: in fact, we got a tracing paper from a 2.5-inch SATA model, but squeezed into the frame of an M.2 size card. Therefore, from the point of view of the M.2 architecture, the Crucial M550 is not at all surprising. This drive is based on the Marvell 88SS9189 controller, which uses Micron's MLC NAND, manufactured according to 20nm standards.

Recall that until recently the Crucial M550 was the flagship drive of this manufacturer, so the engineers not only provided it with an advanced controller, but also sought to give the flash memory array the maximum level of parallelism. Therefore, modifications of the Crucial M550 up to half a terabyte use MLC NAND with 64-gigabit cores.

For testing, we received a 128 GB Crucial M550 sample. This drive is an M.2 card of the typical 2280 format, which is equipped with two type B and M keys. This means that you can install this drive in any slot, but for it to work, this slot must support a SATA interface through which any versions of Crucial work M550.

Crucial M550 128GB (CT128M550SSD4)

The board of the Crucial M550 128 GB drive we received is of interest because all the microcircuits on it are located only on one side. This allows it to be successfully used in ultra-thin portable systems in the so-called single-sided S2 / S3 slots, where the back surface of the drive circuit board is pressed against the motherboard. For most users, this does not matter, but, unfortunately, the struggle to reduce the thickness turned into the fact that capacitors had to be removed from the drive, which provide an additional guarantee of data integrity during sudden power outages. There are vacant places for them on the printed circuit board, but they are empty.

The entire 128GB Crucial M550 flash storage array is housed in two chips. Obviously, in this case, chips are used that contain eight 64-gigabit semiconductor crystals. This means that the Marvell 88SS9189 controller on the SSD model in question can use 2x interleaving. The 256 MB LPDDR2-1067 chip is used as RAM.

The M.2 versions of the Crucial M550, as well as the Crucial M500, along with their more impressive looking 2.5-inch counterparts, support AES-256 hardware data encryption without causing performance degradation. Moreover, it fully complies with the Microsoft eDrive specification, which means that you can manage flash memory encryption directly from the Windows environment, for example, using the standard BitLocker tool.

Kingston SM2280S3

Kingston has chosen a somewhat non-standard path for mastering the M.2 SSD niche. She did not release M.2 versions of the models she already had, but designed a separate SSD, which has no analogues in other form factors. Moreover, not the second-generation SandForce controller, which Kingston continues to install in almost all of its 2.5-inch flash drives, was chosen as the hardware platform, but the Phison PS3108-S8 chip, which was chosen as a budget platform by third-tier SSD manufacturers. And this means that, despite its uniqueness, the Kingston SM2280S3 is not something special: it is aimed at the lower price segment, and its controller has a SATA interface and, of course, does not use all the features of M.2.

For testing, we were given a 120-gigabyte version of this drive. It looks like this.

Kingston SM2280S3 120GB (SM2280S3/120G)

As the name implies, this SSD uses an M.2 2280 format board. And since it works via the SATA 6 Gb / s interface, the drive's knife connector has two cutout keys at once: type B and type M. That is, physically install the Kingston SM2280S3 can be in any M.2 slot, but it will require support for this SATA interface in order to work.

In terms of hardware configuration, the Kingston SM2280S3 is similar to numerous 2.5-inch flash drives with a similar controller. Among them, we, for example, considered Silicon Power Slim S55. Like the Silicon Power product, the Kingston SM2280S3 is equipped with flash memory from Toshiba. Although the microcircuits installed on the SSD in question are relabeled, by indirect evidence, with a high degree of certainty, it can be argued that they use 64-gigabit MLC NAND crystals manufactured using a 19-nm process technology. Thus, the eight-channel Phison PS3108-S8 controller in the Kingston SM2280S3 can use two device interleaving in each of its channels. In addition, the SSD board also has a 256 MB DDR3L-1333 SDRAM chip, which works in tandem with the controller and is used by it as RAM.

An interesting feature of the Kingston SM2280S3 is that the manufacturer claims an extremely long resource for it. The official specifications allow 1.8 times the capacity of this SSD to be written to daily. True, performance in such harsh conditions is guaranteed only for three years, but this still means that up to 230 TB of data can be written to a 120 GB Kingston M.2 drive.

Plextor M6e

Plextor M6e is a solid state drive, which we have already written about more than once, but as a solution installed in PCI Express slots. However, along with such heavyweight versions, the manufacturer also offers M.2 versions of M6e, since those drives that are proposed to be installed in PCI Express slots are actually assembled on the basis of miniature cards in the M.2 form factor. But the most interesting thing about the Plextor drive is not even that, but the fact that it is fundamentally different from all other participants in the review using the PCI Express bus, and not the SATA interface.

In other words, in the Plextor M6e we have a flagship device, the performance of which is not limited to the bandwidth of SATA 600 MB / s. It is based on an eight-channel Marvell 88SS9183 controller that transmits data from the SSD over two PCI Express 2.0 lanes, which in theory allows you to achieve a maximum throughput of about 800 MB / s. From the flash memory side, the Plextor M6e is similar to many other modern SSDs: it uses Toshiba's MLC NAND, which is manufactured using the first-generation 19-nm process technology.

Two versions of the Plextor M6e in M.2 version took part in our testing at once: 128 and 256 GB.

Plextor M6e 128GB (PX-G128M6e)

Plextor M6e 256GB (PX-G256M6e)

Both M.2 drive options are located on 22 × 80 mm cards. Moreover, please note that their blade connector has cutouts in the B and M key positions. And although, according to the specification, the Plextor M6e, which uses the PCIe x2 bus for connection, should have had only one type B key, the developers added a second key to it for compatibility. . As a result, Plextor M6e can also be installed in slots connected to four PCIe lanes, but the drive, of course, will not work faster from this. Therefore, M6e is primarily suitable for those M.2 slots that are found on many modern motherboards based on Intel's H97 / Z97 chipsets and are powered by a pair of PCIe chipset lines.

In addition to the Marvell 88SS9183 controller, the M6e boards have eight flash memory chips from Toshiba. In the 128 GB version of the drive, these chips contain two 64-gigabit MLC NAND crystals, and in the 256 GB drive, each chip contains four such cores. Thus, in the first case, the controller uses a two-fold interleaving of devices in its channels, and in the second - a four-fold interleaving. In addition, the boards also have a DDR3-1333 chip that plays the role of RAM. Its capacity is different - 256 MB for the younger version of the SSD and 512 MB for the older one.

Although the use of M.2 slots and the PCI Express bus for connecting SSDs is a relatively new trend, there are no compatibility issues with the Plextor M6e. Since they work through the standard AHCI protocol, when they are installed in compatible M.2 slots (that is, those that support PCIe drives), they are detected in the motherboard BIOS along with regular drives. Accordingly, there are no problems in assigning them as starting devices, and the operating system does not require special drivers for the M6e to work. In other words, these M.2 PCIe SSDs look exactly the same as their M.2 SATA counterparts.

SanDisk X300s

SanDisk follows the same strategy as Crucial for M.2 drives - it repeats its 2.5-inch SATA SSDs in this format. However, this does not apply to all consumer products, but only to business models. This also applies to the SanDisk X300s made in the M.2 form factor - we are dealing with a drive based on the four-channel Marvell 88SS9188 controller and SanDisk's proprietary MLC flash memory, manufactured using the second-generation 19-nm process technology.

Do not forget that the SanDisk X300s, like any other SSD from this manufacturer, has one more feature - nCache technology. Within its framework, a small part of MLC NAND operates in fast SLC mode and is used for caching and consolidating write operations. This allows the X300s to deliver decent performance even with a quad-channel controller architecture.

For testing, we were given a sample of SanDisk X300s with a capacity of 256 GB. He looked like this.

SanDisk X300s 256GB (SD7UN3Q-256G-1122)

It immediately catches your eye that the drive card is single-sided, that is, it is also compatible with the “thin” M.2 slots that are used in some ultrabooks, allowing you to save an additional one and a half millimeters of thickness. Otherwise, nothing unusual: the board format is the usual 22 × 80 mm, for maximum mechanical compatibility, the blade connector is equipped with both types of key cutouts. The SanDisk X300s requires an M.2 slot with support for SATA 6 Gb / s, that is, in this case we again have a drive in a new format, but working according to the old rules and not using the opening data transfer capabilities via the PCI Express bus.

On the SanDisk X300s 256 GB board, in addition to the Marvell 88SS9188 base controller and RAM chip, four flash memory chips are installed, each of which has eight 19-nm MLC NAND semiconductor crystals with a volume of 64 Gb. Thus, the controller uses eight interleaving devices, which ultimately gives a fairly high degree of parallelism of the flash memory array.

The SanDisk X300s drive model is unique not only in its hardware architecture, which is based on a four-channel controller from Marvell. Focusing on business use, it can offer enterprise-grade hardware-based data encryption that does not introduce any delays into the operation of the SSD. The AES-256 hardware engine not only complies with TCG Opal 2.0 and IEEE-1667 specifications, but is also certified by leading enterprise data protection software vendors such as Wave, McAfee, WinMagic, Checkpoint, Softex and Absolute Software.

Transcend MTS600 and MTS800

We combined the story of two drives from Transcend, because, according to the manufacturer, they are almost completely identical in terms of architecture. Indeed, they use a similar element base and claim the same performance indicators. The differences, according to the official version, lie only in the different sizes of M.2 cards on which they are assembled. The MTS600 and MTS800 are based on the proprietary Transcend TS6500 chip, which is actually a relabeled Silicon Motion SM2246EN controller. And this means that the M.2 SSDs from Transcend that came to us for tests are similar in their filling to the rather popular 2.5-inch drive SSD370 offered by the same company. Thus, Transcend's M.2 flash drives, like many other models participating in our testing, use the SATA 6 Gb / s interface.

It should be emphasized that the Silicon Motion SM2246EN controller is usually used in budget products, since it has a four-channel architecture. It is with such an eye that the Transcend MTS600 and MTS800 were designed. Together with a simple controller, these SSDs also use low-cost 20nm flash memory with 128Gb cores from Micron, as a result of which the MTS600 and MTS800 turned out to be one of the cheapest M.2-format SSDs in today's testing.

We tested Transcend MTS600 and MTS800 with a capacity of 256 GB. I must say that in appearance they turned out to be completely different from each other.

Transcend MTS600 256GB (TS256GMTS600)

Transcend MTS800 256GB (TS256GMTS800)

It's a matter of size: the MTS600 model uses the M.2 2260 format, and the MTS800 uses the M.2 2280 format. This means that the length of the cards of these SSDs differs by as much as 2 cm. But the blade connector for both drives is the same and is equipped with two grooves in positions B and M. Accordingly, there are no mechanical compatibility restrictions, however, these SSDs require support for the M.2 SATA interface in order to work.

Both drives are equipped with a Transcend TS6500 controller and a 256 MB DDR3-1600 SDRAM chip used as RAM. But the flash memory chips of the drives are unexpectedly different, which is clearly seen from their marking. The number and organization of these chips are the same: four chips, each containing four 128-gigabit MLC NAND devices, manufactured using a 20-nm process technology. The differences are that they use different voltage levels and have slightly different timings. Thus, despite the manufacturer's assurances, the MTS600 and MTS800 still differ somewhat in their characteristics: the first SSD of this pair has memory with a slightly lower latency. However, perhaps this is not due to some subtle marketing calculation, but to the fact that different batches of drives can be installed with different memory.

An interesting fact: Transcend decided to take Kingston's tactics and began to guarantee a very impressive resource for their SSDs. For example, for the models under consideration with a capacity of 256 GB, the possibility of recording up to 380 TB of data is promised. This is significantly more than the declared endurance of market leaders.

⇡ Comparative characteristics of tested SSDs

	Crucial M500 120 GB	Crucial M500 240 GB	Crucial M550 128 GB	Kingston SM2280S3 120 GB	Plextor M6e 128 GB	Plextor M6e 256 GB	SanDisk X300s 256 GB	Transcend MTS600 256 GB	Transcend MTS800 256 GB
Form Factor	M.2 2280	M.2 2280	M.2 2280	M.2 2280	M.2 2280	M.2 2280	M.2 2280	M.2 2260	M.2 2280
Interface	SATA 6Gb/s	SATA 6Gb/s	SATA 6Gb/s	SATA 6Gb/s	PCIe 2.0x2	PCIe 2.0x2	SATA 6Gb/s	SATA 6Gb/s	SATA 6Gb/s
Controller	Marvell 88SS9187	Marvell 88SS9187	Marvell 88SS9189	Phison PS3108-S8	Marvell 88SS9183	Marvell 88SS9183	Marvell 88SS9188	Silicon Motion SM2246EN	Silicon Motion SM2246EN
DRAM cache	256 MB	256 MB	256 MB	256 MB	256 MB	512 MB	512 MB	256 MB	256 MB
Flash memory		Micron 128Gb 20nm MLC NAND	Micron 64Gb 20nm MLC NAND		Toshiba 64Gb 19nm MLC NAND	Toshiba 64Gb 19nm MLC NAND	SanDisk 64Gb A19nm MLC NAND	Micron 128Gb 20nm MLC NAND	Micron 128Gb 20nm MLC NAND
Sequential Read Speed	500 MB/s	500 MB/s	550 MB/s	500 MB/s	770 MB/s	770 MB/s	520 MB/s	520 MB/s	520 MB/s
Sequential write speed	130 MB/s	250 MB/s	350 MB/s	330 MB/s	335 MB/s	580 MB/s	460 MB/s	320 MB/s	320 MB/s
Random Read Speed	62000 IOPS	72000 IOPS	90000 IOPS	66000 IOPS	96000 IOPS	105000 IOPS	90000 IOPS	75000 IOPS	75000 IOPS
Random write speed	35000 IOPS	60000 IOPS	75000 IOPS	65000 IOPS	83000 IOPS	100000 IOPS	80000 IOPS	75000 IOPS	75000 IOPS
Write resource	72 TB	72 TB	72 TB	230 TB	N/A	N/A	80 TB	380 TB	380 TB
Guarantee period	3 years	3 years	3 years	3 years	5 years	5 years	5 years	3 years	3 years

Test Methodology

Testing is carried out in the Microsoft Windows 8.1 Professional x64 with Update operating system, which correctly recognizes and maintains modern solid state drives. This means that in the process of passing the tests, as in normal everyday use of the SSD, the TRIM command is supported and actively involved. Performance measurement is performed with drives in a "used" state, which is achieved by pre-filling them with data. Before each test, the drives are cleaned and maintained using the TRIM command. Between individual tests, a 15-minute pause is maintained, allotted for the correct development of garbage collection technology. All tests, unless otherwise noted, use random incompressible data.

Applications and tests used:

Iometer 1.1.0

Measuring the speed of sequential reading and writing data in blocks of 256 KB (the most typical block size for sequential operations in desktop tasks). Estimates of speeds are performed within a minute, after which an average is calculated.
Measuring the speed of random reading and writing in blocks of 4 KB (this block size is used in the vast majority of real operations). The test is carried out twice - without a request queue and with a request queue with a depth of 4 commands (typical for desktop applications that actively work with a forked file system). The data blocks are aligned with the flash memory pages of the drives. Speeds are evaluated for three minutes, after which an average is calculated.
Establishing the dependence of random read and write speeds when the drive is working with 4-kilobyte blocks on the depth of the request queue (in the range from one to 32 commands). The data blocks are aligned with the flash memory pages of the drives. Speeds are evaluated for three minutes, after which an average is calculated.
Establishing the dependence of random read and write speeds when the drive is working with blocks of different sizes. Blocks from 512 bytes to 256 KB are used. The depth of the request queue during the test is 4 commands. The data blocks are aligned with the flash memory pages of the drives. Speeds are evaluated for three minutes, after which an average is calculated.
Measuring performance under a mixed multi-threaded load and establishing its dependence on the ratio between read and write operations. Sequential reads and writes of 128 KB blocks are used, performed in two independent streams. The ratio between reads and writes varies in 10 percent increments. Speeds are evaluated for three minutes, after which an average is calculated.
Investigation of SSD performance degradation when processing a continuous stream of random write operations. Blocks of 4 KB and a queue depth of 32 commands are used. The data blocks are aligned with the flash memory pages of the drives. The duration of the test is two hours, instantaneous speed measurements are taken every second. At the end of the test, the ability of the drive to restore its performance to its original values is additionally checked due to the operation of the garbage collection technology and after the TRIM command has been processed.

CrystalDiskMark 3.0.3b
Synthetic benchmark that provides typical SSD performance measured on a 1 GB area of the disk "on top" of the file system. From the entire set of parameters that can be evaluated using this utility, we pay attention to the speed of sequential read and write, as well as the performance of random reads and writes in 4-kilobyte blocks without a request queue and with a queue of 32 instructions deep.
PC Mark 8 2.0
A test based on emulating real disk load, which is typical for various popular applications. On the tested drive, a single partition is created in the NTFS file system for the entire available volume, and the Secondary Storage test is carried out in PCMark 8. As test results, both the final performance and the speed of execution of individual test traces generated by various applications are taken into account.
File Copy Tests
This test measures the speed of copying directories with files of various types, as well as the speed of archiving and unzipping files inside the drive. For copying, a standard Windows tool is used - the Robocopy utility, for archiving and unzipping - the 7-zip archiver version 9.22 beta. Three sets of files participate in the tests: ISO - a set that includes several disk images with software distributions; Program - a set that is a pre-installed software package; Work is a set of work files that includes office documents, photographs and illustrations, pdf files, and multimedia content. Each of the sets has a total file size of 8 GB.

⇡ Test bench

As a test platform, a computer with an ASUS Z97-Pro motherboard, a Core i5-4690K processor with an integrated Intel HD Graphics 4600 graphics core and 16 GB DDR3-2133 SDRAM is used. This motherboard has a regular M.2 slot, in which the drives are tested. It should be emphasized that this M.2 slot is served by means of the Intel Z97 logic set and supports SATA 6 Gb / s and PCI Express 2.0 x2 modes. Considering that all SSDs participating in this comparison use either the first or the second connection option, the capabilities of this slot in the context of this test are quite enough. The operation of SSDs in the operating system is provided by the Intel Rapid Storage Technology (RST) 13.2.4.1000 driver.

The volume and speed of data transfer in benchmarks are indicated in binary units (1 KB = 1024 bytes).

⇡ Test participants

The full list of M.2 drives that took part in this comparison is as follows:

Crucial M500 120GB (CT120M500SSD4, Firmware MU05);
Crucial M500 240 GB (CT120M500SSD4, Firmware MU05);
Crucial M550 128GB (CT128M550SSD4, Firmware MU02);
Kingston SM2280S3 120 GB (SM2280S3/120G, Firmware S8FM06.A);
Plextor M6e 128 GB (PX-G128M6e, firmware 1.05);
Plextor M6e 256 GB (PX-G256M6e, firmware 1.05);
SanDisk X300s 256GB (SD7UN3Q-256G-1122, firmware X2170300);
Transcend MTS600 256GB (TS256GMTS600, Firmware N0815B);
Transcend MTS800 256GB (TS256GMTS800, N0815B).

⇡ Performance

Sequential read and write operations

It must be said right away that since M.2 drives do not have any fundamental differences from conventional 2.5-inch or PCI Express models, and use the same interfaces for connection, their performance is generally similar to the performance of SSDs we are used to. In particular, the sequential read speed, as is usually the case, approaches the interface bandwidth, and both Plextor M6e modifications that operate via the PCIe x2 bus are ahead in this parameter.

The write speed is determined by the features of the internal structure of specific models, and here the Plextor M6e and SanDisk X300s 256-gigabyte drives are in the first place. It just so happens that most of the drives in our test are mid-range and low-end models, so very few SSDs give out more than 400 MB / s when writing.

Random reads

Curiously, when measuring random read performance, the PCIe x2-equipped Plextor M6e 256GB loses first place to the SanDisk X300s 256GB flash drive with efficient nCache technology. In other words, it turns out that M.2 SSDs using a SATA connection can compete on equal terms with PCIe x2 models, at least with those that are on the market at the moment. By the way, of the 128 GB solid state drives, the best performance is also not the Plextor product, but the Crucial M550.

A more detailed picture can be seen in the following graph, which shows how SSD performance depends on the depth of the request queue when reading 4-kilobyte blocks.

With the increase in the depth of the request queue, Plextor drives still take the lead, but it should be understood that in real tasks this depth rarely exceeds four commands. The same graph clearly shows the weaknesses of those SSDs that are built on quad-channel controllers. As the load increases, their results scale much worse, so such products should not be used in applications where processing of complex multi-threaded accesses is necessary.

In addition to this, we suggest looking at how the speed of random reading depends on the size of the data block:

Reading in large blocks allows you to again face the limitations that the SATA interface creates. Drives using it in the M.2 form factor show noticeably worse results than their counterparts of the same format, but working through PCIe x2. Moreover, their superiority begins already at 8-kilobyte blocks, which indicates a clear demand for a fast bus.

Random Writes

Random write performance is largely determined by the speed of flash memory used in drives. And it just so happens that the top places on the charts were occupied by those SSDs that are based on Micron's MLC NAND. But the most surprising thing is that the Crucial M550 128 MB stands out for the best performance, even despite its small volume, which does not allow the controller to use the most efficient interleaving of flash memory devices in its channels.

In general, the dependence of the speed of random writing in 4-kilobyte blocks on the depth of the request queue is as follows:

The high performance of the Crucial M550 is evident at any but the maximum depth of the operation queue. But the drives of the same manufacturer, but from the previous M500 line, on the contrary, are characterized by an extremely low speed when writing data.

The following graph shows random write performance versus data block size.

If when reading large blocks, Plextor drives showed the highest performance due to the higher bandwidth of the interface they use, then when writing, only the 256 GB version of the M6e shines with high performance. A similar SSD of half the volume is no better than other models that work via SATA, among which, by the way, the Crucial M550 128 GB stands out again. This SSD appears to be the most efficient SSD for write-dominated environments.

As the cost of solid-state drives is no longer used as exclusively system drives and become ordinary work drives. In such situations, the SSD receives not only a refined load in the form of writes or reads, but also mixed requests, when read and write operations are initiated by different applications and must be processed simultaneously. However, full-duplex operation for modern SSD controllers remains a significant problem. When mixing reads and writes in the same queue, the speed of most consumer-grade SSDs sags noticeably. This was the reason for a separate study, in which we check how SSDs perform when it is necessary to process sequential operations interspersed. The following chart shows the most typical case for desktops, where the ratio of the number of reads and writes is 4 to 1.

Both Plextor M6e hold the lead here. They are strong in sequential read operations, and mixing them with some small fraction of write operations does not harm these drives at all. In second place is the Crucial M550: it held steady in clean operations and continues to show good performance, including in mixed workloads.

The following graph gives a more detailed picture of mixed load performance, showing how SSD speed depends on the ratio of reads and writes to it.

With those ratios between read and write operations, where the speed of the SSD is not determined by the interface bandwidth, the results of almost all test participants get into a close group, from which only three outsiders lag behind: Crucial M500 120 GB, SanDisk X300s 256 GB and Kingston SM2280S3 120 GB.

PCMark 8 2.0 Real Use Cases

The test package Futuremark PCMark 8 2.0 is interesting in that it is not of a synthetic nature, but on the contrary, it is based on the work of real applications. During its passage, real scenarios of disk usage in common desktop tasks are reproduced and the speed of their execution is measured. The current version of this test simulates a workload that is taken from actual Battlefield 3 and World of Warcraft gaming applications and software packages from Abobe and Microsoft: After Effects, Illustrator, InDesign, Photoshop, Excel, PowerPoint, and Word. The final result is calculated as the average speed that the drives show when passing the test tracks.

The first two places in PCMark 8 are won by Plextor M6e with a capacity of 128 and 256 GB. It turns out that during real work in applications, these drives, whose strength is not the use of the SATA interface, but PCIe x2, still outperform other M.2 SSDs based on the architecture borrowed from 2.5-inch models. And among the much cheaper SATA models, the best performance is given by the Crucial M550 120 GB and the SanDisk X300s 256 GB, that is, those SSDs that are based on Marvell controllers.

The integral result of PCMark 8 should be supplemented with performance indicators issued by flash drives when passing individual test tracks, which simulate various variants of a real load. The fact is that under different loads, flash drives often behave a little differently.

Plextor drives show excellent performance in any applications from the PCMark 8 list. Unfortunately, SATA SSDs can only compete with them in World of Warcraft. However, this is primarily due not to the fact that the Plextor M6e is capable of delivering unattainable speed, but to the fact that among the M.2 SATA SSD models we received for testing there were no, for example, Samsung offers or new Crucial drives, which are quite capable of competing at speed with a PCIe x2-powered Plextor M6e drive.

Copying files

Bearing in mind that solid-state drives are being introduced into personal computers more and more, we decided to add to our methodology the measurement of performance during normal file operations - when copying and working with archivers - that are performed "inside" the drive. This is a typical disk activity that occurs if the SSD does not play the role of a system drive, but a regular disk.

Copying, as another example of a real workload, once again brings Plextor drives operating through the PCIe x2 bus to the forefront. Of the models with SATA interface, the Crucial M550 128 GB and Transcend MTS600 256 GB can boast of the best results. By the way, please note that this Transcend SSD model in real work turned out to be noticeably better than the Transcend MTS800, so these drives are still not quite identical in terms of performance.

The second group of tests was carried out during archiving and unzipping the directory with working files. The fundamental difference in this case is that half of the operations are performed with disparate files, and the other half with one large archive file.

Here the situation differs from copying only in that SanDisk X300s 256 GB is added to the number of SATA drive models that demonstrate relatively good performance.

How TRIM and background garbage collection work

When testing various SSDs, we always check how they process the TRIM command and whether they are able to collect garbage and restore their performance without support from the operating system, that is, in a situation where the TRIM command is not transmitted. Such testing was carried out this time as well. The scheme of this test is standard: after creating a long continuous load on data writing, which leads to degradation of the write speed, we disable TRIM support and wait 15 minutes, during which the SSD can try to recover on its own due to its own garbage collection algorithm, but without outside help operating system, and measure the speed. Then the TRIM command is forcibly sent to the drive - and after a short pause, the speed is measured again.

The results of such testing are shown in the following table, where for each tested model it is indicated whether it responds to TRIM by clearing an unused part of the flash memory and whether it can prepare clean flash memory pages for future operations if the TRIM command is not given to it. For drives that turned out to be able to carry out garbage collection without the TRIM command, we also indicated the amount of flash memory that was independently released by the SSD controller for future operations. For the case of operating the drive in an environment without TRIM support, this is just the amount of data that can be stored on the drive at a high initial speed after idle time.

	TRIM	Without TRIM
	TRIM	Garbage collection	Free flash memory
Crucial M500 120 GB	Working	Working	0.9 GB
Crucial M500 240 GB	Working	Working	1.7 GB
Crucial M550 128 GB	Working	Working	1.8 GB
Kingston SM2280S3 120 GB	Working	Working	7.6 GB
Plextor M6e 128 GB	Working	Working	1.9 GB
Plextor M6e 256 GB	Working	Working	12.7 GB
SanDisk X300s 256 GB	Working	Does not work	-
Transcend MTS600 256 GB	Working	Working	2.7 GB
Transcend MTS800 256 GB	Working	Working	2.7 GB

All M.2 drives that have passed our testing process the TRIM command normally. Yes, and it would be strange if in 2015 one of the SSDs suddenly could not cope with such, one might say, a basic function. But with a more difficult task - garbage collection without support from the operating system - the situation is different. The most efficient algorithms that allow you to proactively free up the largest amount of flash memory for future recordings are the Kingston SM2280S3 based on the Phison S8 controller and the 256 GB Plextor M6e with the Marvell 88SS9183 controller. Curiously, the 128 GB version of the Plextor PCIe drive performs much less efficient garbage collection. However, in any case, almost all of the tested drives during idle times are reorganizing data in flash memory and preparing it for the rapid execution of subsequent operations. There is only one exception - SanDisk X300s 256 GB, for which garbage collection does not work in principle without TRIM.

That said, it should be recalled that for modern SSDs, the need for garbage collection that works without TRIM can be called into question. All current versions of common operating systems support TRIM, so it would be wrong to assume that the SanDisk X300s, in which offline garbage collection does not work, is fundamentally worse than the other SSDs featured in this review. In everyday use, such a feature of it is unlikely to be able to manifest itself in any way.

⇡ Conclusions

So, the variety of ways to equip personal computers with solid state drives has increased. In addition to the three already familiar options - connecting to a SATA port, to an mSATA slot, or installing to a PCI Express slot - another one has been added: SSDs in the form of M.2 form factor boards have appeared on sale, and in various platforms you can now often find the corresponding connectors . The question involuntarily arises: are M.2 drives better than all other types of SSD or worse?

In theory, the M.2 standard does indeed offer more options than other types of connectivity. And the point here is not only that M.2 cards are compact, have a size convenient for placing flash memory chips and can be used in platforms that are completely different in their purpose and level of portability. M.2 is also a more flexible and forward-looking standard. It allows the system to interact with SSDs using both the traditional SATA protocol and the PCI Express bus, which opens up space for the industry to create faster flash drives, the maximum speed of which is not limited to 600 MB / s and data exchange with which is not necessary. runs on the AHCI protocol with high overhead.

Another thing is that in practice all this splendor has not yet been fully revealed. The models of M.2 drives available today are for the most part based on exactly the same architecture as their 2.5-inch counterparts, which means they work through the same SATA interface that has set the teeth on edge. Almost all of the SSDs we reviewed in the M.2 form factor turned out to be analogues of any models of the usual format, and therefore they offer characteristics that are quite typical for mass solid-state drives, including the level of performance. The only native M.2 drive among products available in domestic stores is only Plextor M6e, which works via the PCIe x2 interface, due to which it shows the best speed in sequential operations than all its competitors. But even it cannot be called an ideal SSD in M.2 format: the Plextor M6e uses a relatively weak controller, which causes its low performance under random access loads.

So is it worth trying to fill the M.2 slot with an SSD if it is present on your motherboard? If we do not take into account those mobile configurations that other SSD options simply do not allow, then, frankly, now there are no clear arguments in favor of a positive answer to this question. However, we cannot give negative arguments either. In fact, by purchasing and installing an M.2 SSD in your system, you will get about the same as if you use a standard 2.5-inch SATA SSD. At the same time, M.2 cards on average cost a little more than full-size drives (sometimes vice versa), but they allow you to get a more compact platform and free up an extra compartment in the case. What is more important in each case is up to you.

But if in the end you decide to purchase an SSD in the M.2 form factor, then among the options available for sale, we recommend paying attention to the following models:

Plextor M6e. The only M.2 drive with PCIe 2.0 x2 interface available in domestic retail. Due to the increased bandwidth of the interface, it demonstrates high speeds during sequential operations, which makes it a high-performance solution even for some types of real workload. Unfortunately, the cost of such an SSD is noticeably higher than that of models operating via SATA.
Crucial M550. An excellent 2.5-inch drive has an almost identical analogue in M.2 format. The compact versions of the Crucial M550 are as fast and omnivorous as the full-sized flash drives of the same name, and the only feature that was lost when moving to M.2 was hardware data integrity protection against sudden power outages.
SanDisk X300s. This drive in the M.2 form factor is also an analogue of a very good 2.5-inch model. It may not be as powerful as flagship SSDs, but its undoubted advantages are a five-year warranty and compatibility with a wide range of enterprise-grade encryption tools.
Transcend MTS600. Transcend's budget drive offers perhaps the best price-performance ratio of any model we've tested. This is what makes it interesting - it is a very worthy solution for low-cost platforms.

Today we’ll talk a little about the already real non-standard SSD. The benefits of using solid state drives have long ceased to argue - today SSDs are recommended to be installed not only by gamers or designers, but by all ordinary users. While the market is waiting for the release of revolutionary controllers that will allow you to take advantage of PCIe to the fullest, simplified analogs of the M.2 format confidently hold the lead in this direction. Initially, the "intermediate" form factor (on the way from SATA to a full-fledged PCIe) managed to find its niche due to several advantages over older standards.

What exactly are the benefits?

First, obviously, speed: M.2 provides operation through the SATA 3.2 (6 Gb / s) interface, and many models support multiple PCIe lanes simultaneously. It is worth mentioning that the controllers do not yet allow you to fully use the latest interface, but the write speed was increased from about 500 to almost 800 MB / s).

Secondly, compactness. If we compare the dimensions of M.2 drives with the previous standard, mSATA, the first in size can be at least a quarter smaller. Originally developed for ultrabooks and portable devices, the standard is now actively supported by manufacturers of motherboards for conventional desktop PCs. In this case, for example, the memory capacity of the line SanDisk X300(represented by our model SanDisk X300 SD7SN6S) grows up to 1TB.

Size comparison of review model with OCZ Trion 100

The third advantage is versatility. As mentioned above, some models have the ability to connect to both PCIe and SATA. Today, the difference in speed is not as noticeable as we would like, but the future is clearly with PCIe. But in addition to M.2 drives, it supports Bluetooth, Wi-Fi and NFC chips.

M.2 slot in Asus Maximus VIII Ranger motherboard

And finally, prevalence: while SATA Express was not widely developed, the M.2 slot managed to find its place in motherboards from leading manufacturers. As you can see, the standard has become a logical evolutionary branch of the development of the use of SSDs, surpassing mSATA and at the same time being the most compact and fastest solution on the market.

Excursion into history

The history of the development of M.2, like any other standard, contains a number of errors and "childhood illnesses": problems that were solved on the experience of early flaws. The first SSD in M.2 can be considered Plextor M6e, not a particularly successful product, but nevertheless gave impetus to development.

It was preceded by other drives (from companies such as Intel, Crucial, KingSpec), but they were designed only for mobile and portable devices. Despite the Plextor M6e's dual-lane PCIe 2.0 capabilities, the new form factor did not deliver the expected performance, and compatibility was hampered by the lack of custom M.2 drives on the market at the time. In fact, it was Plextor who opened this new direction.

An important problem for a long time was the unwillingness of manufacturers to spend money on full-fledged support for PCIe: by assembling drives in the M.2 form factor, they still reduced performance to a minimum. There were only a few models available in stores that supported SATA operation via a 2x or 4x PCIe interface. In this case, the advantage of M.2 over mSATA was only compactness and only slightly increased performance.

In addition, even when using PCIe capabilities, manufacturers resorted to AHCI drivers, although NVM Express is much more beneficial for SSDs.

Gradually, the market began to be filled with models from the manufacturers mentioned above: Crucial M500, Transcend MTS600, Kingston SM2280. However, the form factor of these models can still be called "half M.2": no one wanted to use the capabilities of the new standard to the fullest.

By the way, now the presence of certain keys in the selected drive model can also cause difficulties when buying: it all depends on the user's motherboard. Some boards only support B-keyed drives (2xPCIe), others support M-keyed drives (4xPCIe). It is clear that M is fully compatible with B, but if the "mother" is designed only for models with B-keys, you will have to forget about M-products. The length of the M.2 card will also have to be taken into account: long drives with adapters simply won't fit on some boards.

Samsung is about to complete the development of M.2: the revolutionary Samsung PRO 950 finally switches to 4 PCIe 3.0 interfaces, allowing you to increase the write speed to 1500 MB / s. Samsung has specially developed a new controller that allows you to squeeze the maximum available out of the tire. At 256 GB, the lifespan of a drive is equivalent to a 200 TB rewrite: about 180 GB to be overwritten daily for three years. The drive will go on sale in the near future, and its terabyte version - next year.

X300 - not the fastest, but inexpensive horses

But from expensive new products, let's return to firmly established models and talk about an affordable and successful option - Sandisk X300 128GB

Technology, connection

SanDisk is a well-known player in the storage market. Their proprietary technology nCache 2.0 (allows you to save device resource when working with small-block data; it is programmed at the controller level) has managed to earn positive reviews from critics and experts and is used in many of the manufacturer's drives. Including in the considered X300.
The drive is connected via the SATA 3.2 interface.

This is what the disk board looks like without a container

An important detail, by the way, is this coveted screw, which, of course, is not included with the disk. You need to look for it in the box with the motherboard. There should also be a special platform that is screwed into the board (or it may already be screwed in - depends on the manufacturer).

There are two versions of the drive - 128GB and 512GB with the same screw

The motherboard can accommodate M.2 cards of different lengths. It's great that we got exactly this one in the test - ASUS MAXIMUS VIII. She has several mounts for fixing the board of different lengths.

Sandisk X300 on ASUS MAXIMUS VIII RANGER motherboard

The installed board takes up almost no space in the case. This, of course, is the main advantage in terms of ergonomics - no loops and hard power cables from the PSU in the grid, with which we did not develop friendship.

Test results

We ran several tests with different software: the drive was tested on a system with Windows 10 Pro, an i7 processor and 16 GB of RAM.

Test stand:

OS: Windows 10 Pro
CPU: i7-6700 @ 3.4GHz
RAM: 16GB DDR4 @ 2140MHz
MTHRBRD: ASUS MAXIMUS VIII RANGER

Recall that the read / write speed declared by the manufacturer is 530/470 MB per second.

Test results in Crystal DiskMark:

HD Tune Pro disk check results:

Readings of the HD Tune Pro utility and the standard Windows hard drive diagnostic tool while copying a large file from the OCZ Trion 100 drive to the Sandisk X300 drive:

The results of checking the disk with the AS SSD Benchmark utility:

Hello friends! When assembling a powerful PC, SSD M2 is quite in demand. How to install a solid-state drive of this format and what you should pay attention to in this case, I will tell you in today's publication.

The difference in dimensions

All SSDs in this format have a standard width of 22mm. They differ in length. The longer such a board is, the greater the capacity of the drive, because more chips will fit on its surface, however, such a part will also cost more.

There are several designations for slats of different lengths. Their decoding is simple: the first 2 digits indicate the width, the last two indicate the length of the component. For example, a bar 2242 will have a length of 42 mm, and 2280 - 80 mm, respectively.

The largest bars, 2210, are 110 mm long, so they probably won't fit in a slim case. This is due to the features of the slot we are considering: it is located parallel to other connectors on the motherboard, and the tracks for connection are at the end of the SSD, so the drive is mounted parallel to the motherboard.

The use of such a form factor is already convenient in that it saves the user from unnecessary wires inside the system unit, and the data transfer rate is much higher than that of SATA of any revision.

Connector Features

Although the connector width is standard, there are several types. They differ from each other by the type of key:

Type B - The gap is located on the right side of the PCB, to the left of the host controller. To the right of the gap are 6 more contacts. Such a device also works with PCIe x2 buses.
Type M - the gap is on the left side of the bar, and there are five more pins on the left. Supports PCIe x4 buses to double the throughput.
Type B+M. Both of the above are present. Cards are limited to PCIe x2 speed.

During installation, check whether the key on the SSD corresponds to the slot on the motherboard, because even if you manage to connect such a drive, it will not work.

How to connect the device correctly

The process will take even less time than you read this manual: after carefully unpacking the package and removing the SSD, you should gently insert it into the motherboard without much effort.

If the key types match, the board will easily fit into the slot. It remains only to fix it with a special screw, if such an option is provided for by the design, which is not always the case.

Installing additional drivers in the future is not required: all SSD drives are recognized by the operating system, thanks to the pre-installed AHCI drivers.

If this does not happen, you should go into the BIOS and check the settings for the drives: by default, the IDE type can be set for them. In this case, they will not be recognized, and the operating system, if installed on the SSD, simply will not boot.

Is it possible to connect M2 to another slot

When upgrading a computer, it may happen that there is no M.2 connector on the motherboard. In this case, you can use an adapter that plugs into a PCIe x4 port. There are usually several of them on the motherboard, so there is likely to be a free one.

Samsung Electronics announced the launch of the first Samsung 950 PRO Series M.2 SSD with scalable NVM Express controller(Non-Volatile Memory Express). Let's figure out why Samsung is moving to a new form factor and controller, as well as what is good for the user.

To date, it is M.2 slots that seem to be the most promising for SSDs: they are able to provide the highest throughput among all existing options for connecting solid state drives.

What is NVM?

The biggest problem for SSDs today is the bandwidth limitation of the older Serial ATA and Serial Attached SCSI (SAS) buses. The bandwidth of the latest SATA-III is 600 MB/s, the data transfer rate of Serial Attached SCSI (SAS 12G) is 1.2 GB/s. Modern SSDs are capable of more.

The NVMe protocol speeds up I/O operations by eliminating the SAS command stack (SCSI). NVMe SSDs plug directly into the PCIe bus. Applications get a dramatic performance boost from shifting I/O activity from SAS/SATA SSD and HDD to NVMe SSD. Memory devices of a new type of storage are nonvolatile (non-volatile) and the delay in accessing them is much lower - at the level of delays in random access (volatile) memory.

The NVMe controller demonstrates all the advantages of SSD: very low access latency and huge queue depth for read and write operations. The extremely low latency of storage devices significantly reduces the chances of data table locks during table updates. This is critical for multi-user databases with complex and interrelated tables.

M.2 connector on the motherboard.

Today, NVM Express (NVMe) is supported by all ASUS motherboards based on the Intel Z97 Express and X99 Express chipsets - for this you need to update the UEFI BIOS and use the ASUS Hyper Kit expansion card as an option.

The expansion card allows owners of motherboards based on the X99 chipset to connect 2.5" drives with an NVMe interface - for example, Intel SSD 750 using the SFF-8639 (mini-SAS HD) connector. The drive itself will also have an SFF-8639 connector, it looks like this:

If the motherboard does not have an M.2 connector or it is not possible to use it, there are adapter cards for PCIe:

Supermicro unveiled NVMe-optimized solutions:

The NVMe Virtual SAN-ready SuperServer delivers industry-leading performance and density in a 1U Ultra 10x NVMe solution (SYS-1028U-VSNF series), easily scalable to enterprise, data center, and cloud applications, according to the manufacturer.

The 2U Ultra 24x NVMe SuperServer (SYS-2028U-TN24RT+) increases hot-swap NVMe density and can be shipped in even higher density configurations - up to 24x2.5″ hot-swap NVMe per 1U.

Two new 2U Virtual SAN Ready Node solutions exclusively based on SSD flash, Ultra (SYS-2028U-VSNF series) and TwinPro (SYS-2028TP-VSNF series) architectures support up to 480 virtual machines in 4 nodes.

In general, Supermicro has a whole line of servers for NVMe media, they are still rare on sale, just like the media themselves.

However, back to the Samsung 950 Pro.

Samsung 950 Specification

Samsung 950 Pro
Manufacturer	Samsung
Series	950Pro
Model number	MZVKV256	MZVKV512
Form Factor	M.2 2280
Interface	PCI Express 3.0 x4 - NVMe
Capacity	256 GB	512 GB
Configuration
Memory chips: type, interface, manufacturing process, manufacturer	Samsung 128Gb 32-layer MLC V-NAND
Memory chips: number / number of NAND devices in a chip	2/8	2/16
Controller	Samsung UBX
DRAM buffer: type, size	LPDDR3-1600, 512 MB
Performance
Max. sustained sequential read speed	2200 MB/s	2500 MB/s
Max. sustained sequential write speed	900 MB/s	1500 MB/s
Max. random read speed (blocks of 4 KB)	270000 IOPS	300000 IOPS
Max. random write speed (blocks of 4 KB)	85000 IOPS	110000 IOPS
physical characteristics
Power Consumption: Idle/Read-Write	1.7/6.4W	1.7/7.0W
MTBF (mean time between failures)	1.5 million hours
Write resource	200 TB	400 TB
Dimensions: L × H × D	80.15×22.15×2.38mm
Weight	10 g
Guarantee period	5 years
recommended price	$200	$350

Unlike the Samsung SM951-NVMe OEM drive, the 950 Pro is based on progressive 3D MLC V-NAND. The SM951 uses conventional planar flash memory manufactured using the 16nm process technology.

Very important: The motherboard UEFI BIOS must contain an NVMe driver to boot the OS from the 950 Pro.

The 950 Pro can get quite hot in some cases - at maximum load, this SSD is capable of delivering up to 6-7 watts. At the same time, notes anandtech.com, this is not a serious problem. The official position of the manufacturer on this matter is as follows: The temperature of the 950 Pro rises to the upper limit only in the case of a continuous, long and difficult load, which is not typical for client SSDs. The decrease in performance with a sequential write to a drive of about 100 GB of data is unlikely to affect ordinary users in any way. That is, in the case of using the drive as part of a conventional PC, the problem of overheating is unlikely.».

In most tests anandtech.com 950 Pro performed very well: