Form factor
The form factor of the motherboard determines, first of all, its physical dimensions, and, accordingly, a number of parameters directly related to them: type of computer case, installation method, type of power connector, number of slots for additional boards (expansion slots), etc. At the moment, there are such main form factors of motherboards:
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ATX. One of the most common form factors for PC motherboards. The standard size of such a board is 30.5x24.4 cm, it has up to 7 expansion slots and a 24-pin or (less often, in older models) 20-pin power connector.
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Micro-ATX. A slightly reduced version of the ATX form factor, with more compact dimensions (usually 24.4x24.4 cm) and, accordingly, fewer places for peripherals — there are usually only two slots for "RAM", expansion slots — from two to four. Nevertheless, despite the limited size, such boards can be intended for quite powerful systems.
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Mini-ITX. Motherboards of compact dimensions (17x17 cm). Designed for use primarily in small form factor computers (small form factor, SFF), in other words, compact PCs. According to the mounting specifications and the location of connectors and slots, they are compatible with ATX standard cases. They usually have one expansion slot.
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mini-STX. Another representative of compact form factors, assuming a boar
...d size of 140x147 mm. Thus, the overall size is almost a third smaller than mini-ITX. At the same time, such motherboards often have seats for fairly powerful processors (for example, the LGA 1151 socket for Intel Core chips) and are made based on the corresponding TDP values. But expansion slots, usually, are absent.
— micro DTX. A relatively new compact form factor, which is not common, mainly among rather specific motherboards — in particular, models designed for cases in the PIO form factor. This form factor is characterized by a very small size and weight and allows you to mount the case directly behind the monitor, on a standard VESA mount. One of the features of "motherboards" for such systems is that the graphics card is installed along the board, and not perpendicularly — accordingly, the PCI-E 16x connector (see below) has a non-standard location. At the same time, micro-DTX boards are similar in terms of fasteners to microATX and can be used in cases of the corresponding form factor (except that additional equipment may be required for the correct installation of a graphics card). The standard size of such a board is 170 x 170 mm, similar to mini-ITX.
— mini DTX. An intermediate format between the microDTX described above and the original DTX; sometimes also described as an extended mini-ITX version. It has a standard size of 170 x 203 mm and can be equipped with two expansion slots (mini-ITX and mini-DTX have one such slot); it is completely similar in application — it is intended mainly for compact cases, in particular, HTPC computers.
— XL-ATX. Larger version of the ATX form factor. While not yet a common standard, size options include 32.5x24.4cm with 8 expansion slots and 34.3x26.2cm with up to 9 expansion slots.
— Thin mini-ITX. A “thin” version of the reduced mini-ITX form factor described above: according to the official specification, the total thickness of the thin mini-ITX board should not exceed 25 mm. Also designed for the most miniature computers — in particular, HTPC.
— E-ATX. The letter E in the name of this form factor stands for "Extended" — extended. True to its name, E-ATX is another enlarged version of ATX using 30.5x33cm boards.
— EEB. Full name SSI EEB. The form factor used in server systems (see “By direction”) provides a board size of 30.5x33 cm.
— CEB. The full name is SSI CEB. Another form factor of "server" motherboards. In fact, it is a narrower version of the EEB described above, with a width reduced to 25.9 cm (with the same height of 30.5 cm).
— flex-ATX. One of the compact variations of ATX, which provides board dimensions of less than 229x191 mm, as well as less than 3 expansion slots. At the same time, in terms of the location of the mounting holes, this standard is identical to microATX; in fact, it was developed as a potential replacement for the latter, but for a number of reasons it did not receive much distribution, although it continues to be produced.
— Non-standard (Custom). The name Proprietary is also used. Motherboards that do not conform to standard form factors and are designed for cases of special sizes (usually branded ones).Size (HxW)
Motherboard dimensions in height and width. It is assumed that the traditional placement of motherboards is vertical, so in this case one of the dimensions is called not the length, but the height.
Motherboard sizes are largely determined by their form factors (see above), however, the size of a particular motherboard may differ slightly from the standard adopted for this form factor. In addition, it is usually easier to clarify the dimensions according to the characteristics of a particular motherboard than to look for or remember general information on the form factor. Therefore, size data can be given even for models that fully comply with the standard.
The third dimension — thickness — is considered less important for a number of reasons, so it is often omitted.
1x PCI-E slots
Number of PCI-E (PCI-Express) 1x slots installed on the motherboard. There are
motherboards for 1 PCI-E 1x slot,
2 PCI-E 1x slots,
3 PCI-E 1x ports and even more.
The PCI Express bus is used to connect various expansion cards — network and sound cards, video adapters, TV tuners and even SSD drives. The number in the name indicates the number of PCI-E lines (data transfer channels) supported by this slot; the more lines, the higher the throughput. Accordingly, PCI-E 1x is the basic, slowest version of this interface. The data transfer rate for such slots depends on the PCI-E version (see "PCI Express Support"): in particular, it is slightly less than 1 GB / s for version 3.0 and slightly less than 2 GB / s for 4.0.
Separately, we note that the general rule for PCI-E is as follows: the board must be connected to a slot with the same or more lines. Thus, only single-lane boards will be guaranteed to be compatible with PCI-E 1x.
PCI-E 16x slots
Number of PCI-E (PCI-Express) 16x slots installed on the motherboard.
The PCI Express bus is used to connect various expansion cards — network and sound cards, video adapters, TV tuners and even SSD drives. The number in the name indicates the number of PCI-E lines (data transfer channels) supported by this slot; the more lines, the higher the throughput. 16 lanes is the largest number found in modern PCI Express slots and cards (more is technically possible, but the connectors would be too bulky). Accordingly, these slots are the fastest: they have a data transfer rate of 16 GB / s for PCI-E 3.0 and 32 GB / s for version 4.0 (for more information about the versions, see "PCI Express Support").
Separately, we note that it is PCI-E 16x that is considered the optimal connector for connecting video cards. However, when choosing a motherboard with several such slots, it is worth considering the PCI-E modes supported by it (see below). In addition, we recall that the PCI Express interface allows you to connect boards with a smaller number of lines to connectors with numerous lines. Thus, PCI-E 16x will fit any PCI Express card.
It is also worth mentioning that in the design of modern "motherboards" there are slots of increased sizes — in particular, PCI-E 4x, corresponding in size to PCI-E 16x. However, the type of PCI-E slots in our catalog is indicated by the actual throughput; so only connectors that support 16x speed are considered as PCI-E 16x.
USB 3.2 gen1
The number
of USB 3.2 gen1 connectors provided on the motherboard.
USB connectors (all versions) are used to connect to the "motherboard" USB ports located on the outside of the case (usually on the front panel, less often on the top or side). With a special cable, such a port is connected to the connector, while one connector, usually, works with only one port. In other words, the number of connectors on the motherboard corresponds to the maximum number of case USB connectors that can be used with it. At the same time, we note that in this case we are talking about traditional USB A connectors; connectors for newer USB-C are mentioned separately in the specifications.
Specifically, USB 3.2 gen1 (formerly known as USB 3.1 gen1 and USB 3.0) provides transfer speeds of up to 4.8 Gbps and more power than the earlier USB 2.0 standard. At the same time, USB Power Delivery technology, which allows you to reach power up to 100 W, is usually not supported by this version of USB A connectors (although it can be implemented in USB-C connectors).
Optical S/P-DIF
Output for sound transmission, including multi-channel, in digital form. Such a connection is notable for its complete insensitivity to electrical interference, since an optical cable, rather than an electrical cable, is used to transmit the signal. The main disadvantage of
optical S / P-DIF, in comparison with coaxial, is a certain fragility of the cable — it can be damaged by strongly bending or stepping on it.
USB 2.0
The number of USB 2.0 connectors installed on the back of the motherboard.
Recall that USB is the most popular modern connector for connecting various external peripherals — from keyboards and mice to specialized equipment. And USB 2.0 is the oldest version of this interface that is relevant today; it is noticeably inferior to the newer USB 3.2 both in terms of speed (up to 480 Mbps), and in terms of power supply and additional functionality. On the other hand, even such characteristics are often enough for undemanding peripherals (like the same keyboards / mice); and devices of newer versions can be connected to the connectors of this standard — there would be enough power supply. So this version of USB is still found in modern motherboards, although there are fewer and fewer new models with USB 2.0 connectors.
Note that in addition to the connectors on the rear panel, connectors on the board itself (more precisely, ports on the PC case connected to such connectors) can also provide a USB connection. See below for more on this.
USB 3.2 gen1
The number of native USB 3.2 gen1 connectors provided on the back of the motherboard. In this case, traditional, full-size USB A ports are meant.
USB 3.2 gen1(formerly known as USB 3.1 gen1 and USB 3.0) is a direct successor and development of the USB 2.0 interface. The main differences are a 10-fold increase in the maximum data transfer rate — 4.8 Gbps — as well as higher power supply, which is important when connecting several devices to one port through a splitter (hub). At the same time, peripherals of other versions can be connected to this connector.
The more connectors provided in the design, the more peripheral devices can be connected to the motherboard without the use of additional equipment (USB splitters). There are boards on the market that have
more than 4 USB 3.2 gen1 ports on the back panel. At the same time, we note that in addition to the connectors on the rear panel, connectors on the board itself (more precisely, ports on the case connected to such connectors) can also provide a USB connection. See below for more on this.
USB C 3.2 gen2
The number of
USB-C 3.2 gen2 connectors provided on the back of the motherboard.
USB-C is a relatively new type of connector used in both portable and desktop PCs. It has a small size and a convenient double-sided design, thanks to which the plug can be inserted into the connector in either direction. And version 3.2 gen2 connectivity (formerly known as USB 3.1 gen2 and USB 3.1) is capable of operating at speeds up to 10 Gbps and supports USB Power Delivery technology, which allows you to supply power to external devices up to 100 watts. However, the presence of Power Delivery should be specified separately, this function is not mandatory.
As for the quantity, most often there is only one such port, only a few motherboard models have two USB-C 3.2 gen2 connectors. This is due to the fact that not so many peripherals with a USB-C plug are produced for desktop PCs — full-sized USB A are still more popular. Also note that in addition to the connectors on the rear panel, connectors on the board itself can also provide a USB connection (more precisely, ports on the case connected to such connectors). See below for more on this.