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).VRM heatsink
The design of the motherboard has a separate heatsink for VRM.
VRM is a voltage regulation module through which power from a computer power supply is supplied to the processor. This module steps down the standard power supply voltage (+5V or +12V) to a lower value required by the processor (usually just over 1V). At high loads, the voltage regulator can get very hot, and without a specialized cooling system, the matter can end with overheating and even burnout of parts. The VRM heatsink reduces the likelihood of such situations; it can be useful for any CPU, and highly desirable if the board is planned to be used with a powerful high-end processor (especially overclocked).
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.
DualBIOS
Motherboard support for DualBIOS technology.
Crashes and errors in the BIOS (see BIOS) are one of the most serious problems that can occur with a modern PC — they not only make the computer unusable, but also very difficult to fix.
DualBIOS technology is designed to make it easier to deal with such problems. Motherboards made using this technology have two chips for writing the BIOS: the first chip contains the main BIOS version, which is used to boot the system in normal mode, the second one contains a backup copy of the BIOS in the original (factory) configuration. The backup chip comes into operation if an error is detected in the main BIOS: if an error is detected in the programme code, it is restored to the original factory version, but if there was a hardware failure, the backup chip takes control of the system, replacing the main one. This allows you to keep your system up and running even in the event of serious BIOS problems without resorting to complex recovery procedures.
Max. clock frequency
The maximum RAM clock speed supported by the motherboard. The actual clock frequency of the installed RAM modules should not exceed this indicator — otherwise, malfunctions are possible, and the capabilities of the “RAM” cannot be used to the fullest.
For modern PCs, a RAM frequency of
1500 – 2000 MHz or
less is considered very low,
2000 – 2500 MHz is modest,
2500 – 3000 MHz is average,
3000 – 3500 MHz is above average, and the most advanced boards can support frequencies of
3500 – 4000 MHz and even
more than 4000 MHz.
Max. memory
The maximum amount of RAM that can be installed on the motherboard.
When choosing according to this parameter, it is important to take into account the planned use of the PC and the real needs of the user. So, volumes
up to 32 GB inclusive are quite enough to solve any basic problems and run games comfortably, but without a significant reserve for an upgrade.
64 GB is the optimal option for many professional use cases, and for the most resource-intensive tasks like 3D rendering,
96 GB or even
128 GB of memory will not be a limit. The most “capacious” motherboards are compatible with volumes of
192 GB or
more - they are mainly top-end solutions for servers and HEDT (see “In the direction”).
You can choose this parameter with a reserve – taking into account a potential RAM upgrade, because installing additional RAM sticks is the simplest way to increase system performance. Taking this factor into account, many relatively simple motherboards support very significant amounts of RAM.
AMP
The ability of the motherboard to work with RAM modules that support AMP technology (AMD Memory Profiles). This technology was developed by AMD; it is used in motherboards and RAM blocks and only works if both of these system components are AMP compatible. A similar technology from Intel is called XMP.
The main function of AMP is to facilitate system overclocking (“overclocking”): special overclocking profiles are “sewn” into memory with this technology, and if desired, the user can only select one of these profiles without resorting to complex configuration procedures. This is not only easier, but also safer: every profile added to the bar is tested for stability.
XMP
The ability of the motherboard to work with RAM modules that support
XMP (Extreme Memory Profiles) technology. This technology was developed by Intel; it is used in motherboards and RAM blocks and only works if both of these system components are XMP compliant. A similar technology from AMD is called AMP.
The main function of XMP is to facilitate system overclocking (“overclocking”): special overclocking profiles are “sewn” into the memory with this technology, and if desired, the user can only select one of these profiles without resorting to complex configuration procedures. This is not only easier, but also safer: every profile added to the bar is tested for stability.
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.