What is an m2 slot. What is the difference between SSD sata drives and SSD m2

Whether in the past or this year, articles about SSDs can safely begin with the same passage: “The solid-state drive market is on the verge of serious changes.” For several months now, we have been looking forward to the moment when manufacturers finally begin releasing fundamentally new models of mass-produced SSDs for personal computers, which instead of the usual SATA 6 Gb/s interface will use a higher speed PCI bus Express. 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 fruition. The same single models of consumer SSDs with a bus PCI Express, which do become available, are still clearly experimental in nature and cannot amaze us with their speed.

Being in such anxious anticipation of change, it is easy to lose sight of other events that, although they do not have a fundamental impact on the entire industry, are nevertheless also important and interesting. Something similar just happened to us: new trends have spread unnoticed in the consumer SSD market, to which we have paid almost no attention until now. SSDs of a new format - M.2 - have begun to appear on sale en masse. Just a couple of years ago, this form factor was talked about only as a promising standard, but over the past year and a half it has managed to gain a huge number of supporters both among platform developers and among SSD manufacturers. As a result, today M.2 drives are not a rarity, but an everyday reality. They are produced by many manufacturers, they are freely sold in stores and are installed in computers everywhere. Moreover, the M.2 format has managed to win its place not only in mobile systems for which it was originally intended. Many motherboards For desktop computers today they are also equipped with an M.2 slot, as a result of which such SSDs are actively penetrating classic desktops.

Considering all this, we came to the conclusion that it is necessary to pay close attention to solid-state drives in the M.2 format. 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, among them there are also original products that do not have twins of the classic form factor. Therefore, we decided to catch up and hold a unified summary testing The most popular capacities of M.2 SSD available in domestic stores are 128 and 256 GB. The Moscow company “ Regard", offering an extremely wide range of SSDs, including those in the M.2 form factor.

⇡ Unity and diversity of the world M.2

Slots and cards of the M.2 format (previously this format was called Next Generation Form Factor - NGFF) were initially developed 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 greater flexibility in both logical and mechanical parts. The new standard describes several options for the length and width of cards, and also allows the use of both SATA and the faster PCI Express interface to connect solid-state drives.

There is no doubt that PCI Express will replace the drive interfaces we are used to. Direct use of this bus without additional add-ons allows you to reduce latencies when accessing data, and thanks to its scalability, it significantly increases throughput. Even two PCI Express 2.0 lanes can provide noticeably higher data transfer speeds compared to familiar interface SATA 6 Gb/s, and the M.2 standard allows you to connect to an SSD using up to four PCI Express 3.0 lanes. This foundation for increased throughput will lead to a new generation of high-speed SSDs capable of faster boot times. operating system and applications, as well as reducing delays when moving large amounts of data.

Formally, the M.2 standard is mobile variety SATA Express protocol, described in the SATA 3.2 specification. However, over the past couple of years, M.2 has become much more widespread 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 cannot 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 the M.2 slots that seem to be not only convenient, but also a more promising foundation for future SSDs. Not only are they suitable for both mobile and desktop applications, but they are also capable of delivering the highest throughput of any consumer SSD connectivity option available.

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 options for the corresponding slots is a different story. To begin with, the M.2 form factor SSD boards available on the market are 22mm wide, but come in five lengths: 30, 42, 60, 80, or 110mm. This dimension is reflected in the markings, for example, the M.2 2280 form factor means that the drive card is 22 mm wide and 80 mm long. For M.2 slots, a complete list of dimensions of storage cards with which they can be physically compatible is usually indicated.

The second feature that introduces differentiation into different options M.2 are “keys” in the slot slot and, accordingly, in the blade connector of the cards, which prevent the installation of storage cards in connectors that are logically incompatible with them. At the moment, the M.2 SSD uses two key locations out of eleven different positions described in the specification. Two more options have found application on WLAN and Bluetooth cards in the M.2 form factor (yes, this also happens - for example, wireless adapter Intel 7260NGW), and seven key positions are reserved for the future.

M.2 slots can only have one key cutout, but M.2 cards can have multiple key cutouts at once, making them compatible with multiple types of slots at the same time. The type B key, located instead of pins numbered 12-19, means that no more than two PCI Express lanes are connected to the slot. The M type key, occupying pin positions 59-66, means that the slot has four PCI Express lanes and can therefore provide more high performance. In other words, the M.2 card must not only be the right size, but also have a key layout compatible with the slot. At the same time, the keys not only limit mechanical compatibility between various connectors and boards of the M.2 form factor, but also perform another function: their location prevents incorrect installation drives 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 joining of a slot and connector is only a necessary, but not a sufficient condition for their complete logical compatibility. The fact is that slots with keys B and M can accommodate not only the PCI Express interface, but also SATA, but the location of the keys does not provide any information about its absence or presence. The same applies to M.2 card connectors.

There is one more problem. It lies in the fact that many motherboard developers ignore the requirements of the specifications and install the “coolest” slots with an M type key on their products, but only install two of the four assigned PCIe lanes on them. In addition, the M.2 slots available on motherboards may not be compatible with SATA drives at all. In particular, it is guilty of its love for installing M.2 slots with reduced SATA functionality. ASUS company. SSD manufacturers also adequately respond to these challenges, many of whom 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 presence of the SATA interface in M.2 slots and connectors by external signs alone. That's why full information information about the implementation features 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 yet become completely confusing. In fact, there is currently only one model of M.2 drive with a PCIe x2 interface on the market - Plextor M6e - and one model with a PCIe x4 interface - Samsung XP941. All other flash drives available in stores in the M.2 form factor use the familiar SATA 6 GB/s protocol. Moreover, all M.2 SSDs found in domestic stores have two key cutouts - in positions B and M. The only exception is the 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 fill 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 is the location of the keys on SSD card does the existing M.2 slot in the system allow?
• What is maximum length M.2 card that can be installed in your motherboard?

And only after you can definitely answer all these questions, you can proceed to choosing the appropriate SSD model.

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

What exactly are the benefits?

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

Size comparison of review model with OCZ Trion 100 drive

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 PCIe is clearly the future. But in addition to M.2 drives it supports bluetooth connection, 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 development using SSD, surpassing mSATA and at the same time being the most compact and fastest solution on the market.

Excursion into history

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 capabilities of two PCIe 2.0 lanes used in the Plextor M6e, the drive in the new form factor did not give the expected results in terms of performance, and compatibility was hampered by the lack of custom M.2 drives on the market at that time. In fact, it was Plextor that opened up this new direction.

An important problem for a long time remained the reluctance of manufacturers to spend money on full PCIe support: when 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 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 for SSDs it is much more profitable to use NVM Express.

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 fully use the capabilities of the new standard.

By the way, now the presence of certain keys in the selected drive model can cause difficulties when purchasing: it all depends on the user’s motherboard. Some boards only support drives with B-keys (2xPCIe), some - with M-keys (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: on some boards, long drives with adapters simply will not fit.

Samsung is going 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 bus. At 256GB, the drive's lifespan is equivalent to overwriting 200TB: about 180GB of overwriting daily for three years. The drive will go on sale in the near future, and its terabyte version will be available next year.

X300 – not the fastest, but inexpensive horses

Technology, connection

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

This is what a disk board looks like without a container

An important detail, by the way, is this treasured screw, which, of course, is not included with the disk. You need to look for it in a box with motherboard. There should also be a special pad 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 came across exactly this one in the test – ASUS MAXIMUS VIII. It has several fasteners for fixing boards of different lengths.

Sandisk X300 on motherboard ASUS board MAXIMUS VIII RANGER

The installed board takes up almost no space in the case. This is, of course, the main advantage in terms of ergonomics - no cables or rigid power cables from the power supply in the grid, with which we have no friendship.

Test results

Test stand:

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

Test results in Crystal DiskMark:

Results of disk check using HD Tune Pro utility:

Indications of the HD Tune Pro utility and standard means diagnostics hard drives Windows while copying a large file from an OCZ Trion 100 drive to a Sandisk X300 drive:

Results of checking the disk using the AS SSD Benchmark utility:

They are becoming increasingly popular due to their many benefits. They are miniature in size and do not take up much space in a laptop, mini-PC or desktop computer case (they are installed directly on the motherboard), however, they allow you to achieve speeds inaccessible to “regular” 2.5-inch SSDs.

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

By the way, it’s worth mentioning Intel Optane memory (not to be confused with Intel Optane SSD), which has an M.2 media format, but serves to speed up work HDDs. This technology only works on new Intel platforms, but works surprisingly well, allowing you to significantly increase the speeds of magnetic disks.

M.2 connectors on motherboards may support both standards, or only one - this is worth checking before purchasing so that, for example, you do not try to install a PCIe/NVMe drive into an M.2 connector that only supports the SATA standard. It is worth noting that you can also connect M.2 PCIe drives to the U.2 port (via an adapter) and to the PCI Express slot.

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

Inexpensive M.2 SSD drive

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

WD Green PC SSD G2 (120 GB)

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

Main Features:

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

ADATA XPG SX6000 (128 GB)

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

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 Features:

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

ADATA Ultimate SU800 M.2 (250 GB)

ADATA Ultimate SU800 M.2 drives have a very good price-to-features ratio. Modern 3D TLC Nand memory cells and a 4-channel Silicon Motion SM2258 controller are used.

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

Main Features:

• Capacity: 256 GB
• Interface: SATA III M.2
• Write speed: 520 MB/s
• Read speed: 560 MB/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 - you should not invest in an SSD with a capacity below 240/256 GB. We must also pay attention to the type of interface - whether the media supports the SATA or PCIe interface, and what format (longer, 2280, or shorter, 2260 or 2242).

Crucial MX500 M.2 (250 GB)

The latest generation of SATA SSDs from Crucial, the MX500 is another successful blow to the mid-range performance segment. The M.2 version of the drive has fairly good performance, and the stated speeds reach 560 MB/s when reading and 510 MB/s when writing data. Crucial provides a 5-year warranty (limited to 100TB TBW).

Main Features:

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

Transcend MTS420 (240 GB)

Transcend MTS420 in 240GB version– this is very good offer for users who need M.2 media in the small 2242 format. The manufacturer specified maximum speeds of 560 MB/s for reading and 500 MB/s for writing. It is worth noting that many other discs in this format have worse characteristics. The manufacturer gives it a 3-year warranty.

Main Features:

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

ADATA XPG SX8200 (480 GB)

This is a good offer for laptop users who can install SSD media in M.2 2280 PCIe format 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 Features:

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

Best M.2 SSDs

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

GOODRAM IRDM Ultimate (480 GB)

IRDM Ultimate 480 GB is a good offer for more demanding users. What’s important is that the kit includes an adapter for the PCI Express slot. The manufacturer also installed a heat sink that protects the disk from overheating. On board 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 recording limitation.

Main Features:

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

Intel SSD 760p (512 GB)

Intel SSD 760p are efficient SSD media for desktop computers 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. Maximum speeds are 3230 MB/s for reading and 1625 MB/s for writing. The manufacturer provides a 5-year warranty for the drives, but limited to TBW (288 TB of recording).

Main Features:

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

Samsung SSD 970 EVO (500 GB)

SSD 970 EVO is the third generation of high-speed M.2 media with PCIe interface from Samsung. The 970 EVO models are designed for users who are looking for very fast, but not top-end solutions - we will find this combination in the 970 PRO models. The stated read speed reaches 3400 MB/s, and write speed – 2300 MB/s. The 970 EVO series hard drives come with a 5-year manufacturer's warranty - remember that the previous 960 EVO models only had a 3-year warranty.

Main Features:

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

Samsung SSD 970 PRO (1 TB)

Samsung 970 PRO 512 GB is an absolutely top M.2 PCIe SSD carrier designed for professionals. The manufacturer used here an ultra-reliable MLC memory V-NAND, so users don't have to worry about 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 for reading and 2300 MB/s for writing. The 970 PRO series hard drives come with a 5-year manufacturer's warranty.

Main Features:

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

Samsung Electronics announced the launch of the first solid state drive Samsung series 950 PRO form factor M.2 with scalable NVM Express controller(Non – Volatile Memory Express). Let's figure out why Samsung is moving to a new form factor and controller, and why this is good for the user.

Today, it is the M.2 slots that seem to be the most promising for SSDs: they are capable of providing the highest throughput among all existing options for connecting solid-state drives.

What is NVMe?

The NVMe protocol speeds up I/O operations by eliminating the SAS (SCSI) command stack. NVMe SSDs connect directly to the PCIe bus. Applications receive dramatic performance gains from shifting I/O activity from SAS/SATA SSDs and HDDs to NVMe SSDs. Memory devices of the new type of storage are non-volatile and the latency when accessing them is significantly lower - at the level of latencies of RAM (volatile) memory.

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

The expansion card allows owners of boards 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 disk 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 presented solutions optimized for NVMe:

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

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

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

However, let's return to the Samsung 950 Pro.

Samsung 950 Pro Specification

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

The 950 Pro can get quite hot in some cases - when maximum load This SSD is capable of delivering up to 6-7 W. However, notes anandtech.com, this is not a serious problem. The official position of the manufacturer on this matter is as follows: “ The 950 Pro's temperature rises to the upper limit only under continuous, long-term, and complex workloads, which is not typical for client SSDs. A decrease in performance when sequentially writing about 100 GB of data to a drive once is unlikely to have any impact ordinary users. That is, if the drive is used as part of a regular PC, the problem of overheating is unlikely».

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

Don't know which interface to buy an SSD drive with? Then this article will help you with your choice! Today we will look at what interfaces exist for SSDs.

SSD drives have already been installed in almost all modern gaming PCs and laptops. Not surprising - the storage capacity is increasing, the price is decreasing, and the choice is huge. Yes, not all of them are as good as we would like, but today we will not talk about that. But besides choosing a manufacturer and model, another question arises: what interface do we need a drive with?

Now manufacturers continue development in two directions - the transition from SATA to PCI-Express and the use of a different physical interface. In the second case, several new types of connectors appeared before us. All this can take the user by surprise in case of upgrading his system.

SATA
We are already accustomed to the fact that SSD drives with a SATA interface are 2.5″ devices with a capacity of up to 1 TB. SATA interface III (6 Gbit/s) provides real speed data transfer up to 550 MB/s. Such drives are most often found in PCs, monoblocks and laptops, while having maximum compatibility with platforms. But ultrabooks (for example, ASUS Zenbook) physically cannot accommodate such drives.

PCI-Express
Due to the peculiarity of the physical interface, PCI-Express SSD drives are used exclusively in PCs and servers. Depending on the drive, the PCI-Express x2, x4 or x8 interface is used. Advantage PCI-Express drives is the speed, because it significantly exceeds that available with SATA III (550 MB/s) - here we will already get more than 780 MB/s ( given speed taken from ROG RAIDR Express). And in more expensive solutions - more than a gigabyte per second.

mSATA
The mSATA (mini-SATA) interface can be found on some desktop motherboards (for example, the ASUS Maximus V line) and in a considerable number of laptops. Drives with this interface comply with the SATA III specification (6 Gb/s) and can reach data transfer rates of 550 MB/s. The mSATA interface and devices are externally indistinguishable from the mini-PCI-Express interface and devices, but they are completely incompatible and installing an mSATA device in a mini-PCI-Express slot can lead to failure of these components. Currently, mSATA is already leaving the market, as it was replaced by more new interface— M.2.

SATA Express
The SATA Express interface is designed specifically for PCs and has theoretical throughput 10 Gbps (which is 40% faster than SATA III). The new interface involves the use of a completely different connector on the board and on the drive, as well as the use of a new cable for transmitting information. For example, the new interface is already available on the ASUS Z87 Deluxe/SATA Express motherboard, and will also be available on new motherboards based on the Intel Z97 chipset. True, the drives themselves will appear only by summer. You can connect one SATA Express drive or two SATA III drives to one connector.

M.2 Connector (NGFF)
Previously known as NGFF (Next Generation Form Factor - after mSATA), M.2 drives have taken a place in laptops and ultrabooks. But some desktop motherboards will also have this connector. The M.2 interface can support both PCI-Express lines and SATA lines. But in most cases, PCI-Express lines are used. So when choosing an M.2 drive, you should first find out from the specification of your device what type of M.2 interface you have on the board.