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The interface of the main M.2 connector provided in the laptop.

In this case, the main slot is considered to be the one in which the SSD M.2 drive is installed (see "Drive type"). The interface of the drive itself is indicated separately (see above), and the interface of the connector is specified if the connector supports a more advanced type of connection than the device installed in it. An example is the following situation: the device itself works according to the SATA or PCI-E 3.0 2x standard (see "M.2 drive interface" above), and the connector on the board is capable of working with the PCI-E 3.0 4x interface.

Such information will be useful, first of all, for evaluating the possibilities for upgrading a laptop (with replacing a standard SSD module with a faster one). Nowadays, in this paragraph, you can mainly find the following options:

— PCI-E 3.0 2x. In fact, the most modest PCI-E standard found in M.2 ports of modern laptops: connection using 2 lanes of PCI-E version 3.0. This version provides speeds of about 1 GB/s per line; respectively, two lines give a maximum of just under 2 GB / s.

— PCI-E 3.0 4x. Connection using 4 lanes PCI-E version 3.0. Provides a maximum speed of about 4 GB / s.

— PCI-E 4.0 4x. Connection using 4 lanes PCI-E version 4.0. In this version, the bandwidth, compared to PCI-E 3.0, has been doubled — thus, 4 lines give a maximum speed of about 8 GB / s.

— PCI-E. Connection...via PCI-E, for which the manufacturer did not specify the details (version and number of lines).

Recall that in the case of M.2 connectors, different PCI-E options are quite compatible with each other — except that the speed will be limited by the capabilities of a slower component. In fact, this means that, for example, in an M.2 connector with a PCI-E 3.0 4x interface, it is quite possible to connect a drive for PCI-E 3.0 2x or PCI-E 4.0 4x; in the first case, the speed will be limited by the capabilities of the drive, in the second, by the capabilities of the connector.

The presence in the laptop of an additional compartment for an internal drive of the form factor 2.5 ".

Usually, to install or remove a drive in such a bay, it was not necessary to disassemble the entire laptop — just remove the cover or remove the plug. As for 2.5", this is the traditional form factor for hard drives (HDD) for "laptop" purposes, although other types of media (SSD and SSHD — see "Media Type") can be produced in this format. For connection 2.5 "storage drives normally use the SATA connector — it is not as fast as more modern standards like M.2 PCI-E (see "Drive Interface"), however, it is cheaper, and for HDD this connector is quite enough.

Thus, the presence of an additional 2.5" bay allows you to quickly and cost-effectively increase the total volume of laptop drives.

Connection connectors provided in the design of the laptop.

This paragraph mainly indicates data on video outputs: VGA, HDMI(versions 1.4, 2.0, 2.1 and their varieties), miniHDMI / microHDMI, DisplayPort, miniDisplayPort). In addition, the presence of other types of connectors can be specified here: audio S / P-DIF, service COM port. But information about interfaces such as full-sized USB, USB-C, Thunderbolt and LAN is provided in separate paragraphs (see below).

— VGA. Analogue video output, also known as D-Sub 15 pin. Technically considered obsolete: it has low noise immunity, does not provide sound transmission, and the maximum supported resolution in fact does not exceed 1280x1024. However, VGA inputs are still quite common in monitors today, and are also found in other types of video equipment — in particular, projectors. Therefore, some modern laptops, mainly for multimedia purposes, are equipped with similar outputs — counting on connection to the mentioned video devices.

— HDMI. The most popular modern interface for working with HD content. Uses digital data transmission, a...llows you to transmit high-definition video and multi-channel audio over one cable at the same time. Most modern monitors, TVs, projectors, and other HD-enabled video equipment have at least one HDMI input; so outputs of this type are extremely common in modern laptops.

— microHDMI and miniHDMI. Reduced varieties of the HDMI described above: they are completely similar in functionality and differ only in the size of the connector. They are installed mainly in the thinnest and most compact laptops, for which full-size HDMI is too cumbersome.

The HDMI and mini/microHDMI ports on modern laptops may correspond to different versions:

• v 1.4. The earliest of the commonly used standards, released in 2009. Allows you to transmit a signal in resolutions up to 4096x2160 at a frame rate of 24 fps, and with Full HD resolution, the frame rate can reach 120 fps; 3D video transmission is also possible.
• v 1.4a. The first addition to version 1.4, in which, in particular, two additional 3D video formats were added.
• v 1.4b. The second update of the HDMI 1.4 standard, which introduced only minor clarifications and additions to the v 1.4a specifications.
• v2.0. Global HDMI update introduced in 2013. Also known as HDMI UHD, it allows you to stream 4K video at frame rates up to 60 fps. The number of audio channels can reach 32, and up to 4 audio streams can be broadcast simultaneously. In addition, support for the 21:9 aspect ratio and some improvements regarding 3D content have been introduced.
• v2.0a. First HDMI 2.0 update. A key innovation was compatibility with HDR content (see "HDR support").
• v2.0b. Second update of version 2.0. Key innovations have affected mainly work with HDR — in particular, support for HDR10 and HLG has been added.
• v2.1. One of the newest versions, released in the fall of 2017. Further increases in bandwidth have made it possible to support 4K and even 8K video at frame rates up to 120 fps. In addition, key improvements include enhanced HDR capabilities. Note that to use the full capabilities of HDMI v2.1, HDMI Ultra High Speed cables are required, although basic functions are available with regular cables.

— Display port. Digital high-speed port, allows you to transfer both video and audio in HD quality. It is similar in many respects to HDMI, provides a higher data transfer rate and allows the use of longer cables, but is less common, mainly used in computer technology.

— miniDisplayPort. A smaller version of the DisplayPort described above, designed to make the connector more compact; except for the dimensions, it is no different from the original interface. Some time ago it was a regular video connector for Apple laptops; and even the Thunderbolt interface that replaced it, in versions 1 and 2 (see below), uses a connector identical to the miniDisplayPort connector.

Both full-size DisplayPort and its smaller version may be different versions. Here are the most popular options today:

• v 1.2. The earliest version common in laptops, released in 2010. Among the most important innovations presented in this version are 3D support, the ability to work simultaneously with several video streams for serial connection of screens (daisy chain), as well as the ability to work through the miniDisplayPort connector. Bandwidth v 1.2 is enough to fully support 5K video at 30 frames per second and 8K video — with certain limitations.
• v 1.2a. Update version 1.2, released in 2013. One of the most noticeable innovations is the ability to work with AMD FreeSync (see above). Bandwidth and supported resolutions remain unchanged.
• v 1.3. DisplayPort version released in 2014. Compared to the previous version, the throughput has been increased by 1.5 times for 1 line and almost 2 times for the whole connector (8.1 Gbps and 32.4 Gbps, respectively). This, among other things, made it possible to provide full support for 8K video at 30 fps, as well as increase the maximum frame rate in 4K and 5K standards to 120 and 60 fps, respectively. In daisy chain mode, this standard makes it possible to work with two 4K UHD (3840x2160) screens at a frame rate of 60 Hz, or with four 2560x1600 screens at the same frequency. In addition, Dual-mode support was introduced in this version, providing compatibility with HDMI and DVI interfaces through the simplest passive adapters.
• v 1.4. Version introduced in March 2016. Bandwidth, compared to the previous standard, remained unchanged, but some important features were added — in particular, support for Display Stream Compression 1.2 compression, HDR10 standard and Rec. 2020, and the maximum number of supported audio channels has increased to 32.
• v 1.4a. An update released in 2018 "quietly" — without even an official press release. The main innovation was the update of Display Stream Compression technology from version 1.2 to version 1.2a.

— S/P-DIF. Output for digital audio transmission, including multi-channel. It has two varieties — optical and electrical; the first is absolutely insensitive to interference, but uses rather delicate cables, the second does not require special care in handling, but can be subject to pickups (although the wires are usually made shielded). Laptops use mainly optical S/P-DIF, while for compactness this connector is combined with a mini-Jack jack for connecting headphones. However, anyway, it's ok to clarify the specific features of this interface separately.

— COM port. Universal interface for connecting various external devices — in particular, dial-up modems — as well as for direct connection between two computers. Also known as RS-232 (after the connector). Nowadays it is considered obsolete due to the spread of more compact, faster and more functional interfaces, primarily USB. However, many types of equipment, including specialized ones, use the COM port as a control interface. Such equipment includes uninterruptibles, satellite receivers and communication devices, security and alarm systems, etc. Thus, COM ports, although almost never used in consumer-level laptops, are still found in some specialized models.

A device for working with removable memory cards. Usually, it looks like a characteristic slot right on the laptop case, into which the media is inserted. There are different standards for memory cards, a list of compatible standards is indicated in the note to this item. It is worth noting here that for modern laptops it is almost mandatory to support the SD format and its modifications — SD HC, often also SD XC; other options may also be envisaged, but they have not received such distribution. Anyway, this feature is convenient because memory cards are widely used in other types of electronics: for example, SD is the generally accepted standard in digital cameras, and microSD (compatible with SD slots through simple adapters) is used in smartphones. Accordingly, the presence of a card reader greatly facilitates the exchange of data between a laptop and external devices.

Number of USB 3.2 gen1 ports provided in the laptop. Initially, this interface was called USB 3.0, later USB 3.1 gen1.

Be that as it may, USB is the most popular modern interface for connecting various peripherals to computer - from keyboards, mice and flash drives to very original devices. It can also be used to charge smartphones and other gadgets. And USB 3.2 gen1 is the successor to the popular USB 2.0. In this version, the data transfer speed was increased 10 times - up to 4.8 Gbit/s, and the power supply for external devices was also increased. At the same time, devices with other versions of USB can be connected to the USB 3.2 gen1 port - the main thing is that they have full-size USB A plugs and have enough power for normal operation.

As for the number of USB connectors, the more there are, the more peripherals you can connect to the laptop without using splitters.

The number of USB-C 3.2 gen1 ports provided in the laptop (these connectors were previously labeled USB-C 3.1 gen1 and USB-C 3.0).

USB-C is a relatively new universal connector designed for use in desktop and laptop computers and other devices. It is slightly larger than microUSB, has a convenient double-sided design (it doesn’t matter which side you connect the plug), and also allows you to implement increased power supply and a number of special functions. In addition, the same connector is standardly used in the Thunderbolt interface versions v3 and v4, and technically it can be used for other interfaces; so in some laptops USB-C has a combined purpose — see "Alternate Mode" for more details. And in some models (mostly the most compact ones), USB-C can also charge the device’s own battery.

Specifically, USB-C version 3.2 gen1 allows connection speeds up to 5 Gbps. As for the number of such ports, it is most often small — usually 1 – 2. This is due to the fact that peripherals for USB-C are produced noticeably less than for full-sized USBs. However, in some configurations, the number of connectors of this type can reach 4.

The number of USB C 3.2 gen2 ports provided in the laptop (previously, such connectors were labeled USB C 3.1 gen2 and USB C 3.1).

USB C is universal connector created relatively recently and designed for use in desktop and laptop computers. It is slightly larger than microUSB, has convenient double-sided design (no matter which side the plug is connected to), and also allows for increased power supply and number of special functions. In addition, the same connector is standardly used in the Thunderbolt v3 interface, and technically can be used for other interfaces; so in some laptops USB C has combined purpose - see “Alternate Mode” for more details. And in some laptops (mostly the most compact ones), USB C can also charge the device’s own battery.

Specifically, the USB C 3.2 gen2 version allows for connection speeds of up to 10 Gbps. As for the number of such ports, it is most often small - usually 1 - 2. This is due to the fact that significantly fewer peripherals for USB C are produced than for full-size USB. However, in some configurations the number of connectors of this type can reach 4.

The presence in the laptop of at least one USB-C connector with support for Alternate Mode.

In accordance with the name, Alternate Mode is an alternative mode of operation of the Type C connector, when not USB, but other connection interfaces are implemented through it. The specific set of such interfaces may be different, it should be specified for each model separately. The most typical example is Thunderbolt v3 (see above), such a connection, by definition, works through a USB-C hardware connector. The Thunderbolt specification also includes DisplayPort support, but this video output can be implemented via USB-C and independently, without Thunderbolt functionality. Also, the list of the most popular Alternate Mode options includes HDMI — both in its classic form and in the "mobile" version of MHL (the latter, however, is more typical for smartphones and other handheld equipment than for laptops).

The maximum number of monitors that can be connected to a laptop at the same time and shared.

Simultaneous connection of several screens allows you to expand the visual space available to the user. For example, it can be useful for designers and layout designers when working with large-format materials, for programmers to separate tasks (one monitor for writing code, the second for searching for the necessary information and other auxiliary purposes), and for gamers-enthusiasts — to ensure the maximum immersion effect.