What is the purpose of the motherboard. Appointment of motherboard. Motherboard: What, why and why

The continuation of this series will be this article. Today we will respond to frequently asked questions about the motherboard. You will find out what a motherboard is for what it needs, and the characteristics to which it is worth paying attention to when it is selected. Let's in order.

What is the motherboard computer

Motherboard (mother, mainland, motherboard, main board) - this is the main board of the system unit. It contains connectors for connecting all other parts - video cards, RAM, processor, etc.

Throwing out computer terminology, the motherboard is the base of the entire computer. As we said earlier - and RAM, and the processor play a major role in the computer. Nevertheless, so that they completely disclose their potential, it is necessary to connect the link, which is the motherboard. Let us describe in more detail, for which the computer needs a motherboard.

Why the computer motherboard

Without unnecessary words, we list the main functions of the motherboard:

Combines all the "insides" of the computer among themselves (it is installed on it for a processor, connectors for RAM and a graphics adapter, etc.).
The motherboard turns the mouse, display, system unit, keyboard and other components to a single working ecosystem.
It is responsible for ensuring that the CPU controls the work of other parts of the computer. That is, the motherboard not only turns all PC components to one piece, but also supports the relationship between them.
The motherboard is responsible for the transmission of the picture on the monitor (in the case of integrating a graphics card in it).
The motherboard is responsible for the sound of the computer, since at present the huge number of boards models has a built-in audio card.
Ensuring Internet access - modern motherboards have a built-in network adapter.

What makes the motherboard

Having understood with the previous questions, time to see what the motherboard is. And its main elements can be called:

Processor installation jack ( cPU socket ) - simple words - this is a socket for installing the processor;
Slots PCI and PCI EXPRESS. - The first due to its low performance is used to connect TV tuners, audio and network cards, as well as other devices that are sufficiently bandwidth of this interface. PCI Express is usually used to connect to a PC video card;
Slots under Oz - Here you are installing the RAM bar;
SATA. and IDE Connectors - they serve to connect to a computer of various drives (, SSD). They are also used to connect optical drive drive;
Chipset - This is a set of chips, the so-called North and South Bridges. The Northern Bridge controls the relationship between the system board with RAM, the graphics accelerator, the CPU. And regulates the speed of their work and connects to the southern bridge, which monitors energy saving, BIOS, system clock, IDE, SATA, USB, LAN interfaces, Embeded Audio;
Chip Bios. and nutrition battery CMOS. Memory - here is the software for running a computer and testing it. The CMOS stores the BIOS settings, and so that they do not come down when you turn off the computer (this memory is energy-dependent) uses a special battery that feeds memory.
External connectors are all possible outputs for headphones, microphone, Ethernet, HDMI, USB, etc.;
Power Connectors - Actually, both the motherboard itself and the processor and the cooling system require nutrition.

In principle, this is the main set, which can be found, but it is also necessary to remember that from different manufacturers and models, it may differ, so we turn to the next item.

Types of motherboards and their manufacturers

Today you can see a lot of motherboards from different manufacturers: ASUS, MSI, GIGABYTE, ASRock, Esonic, and all of them are divided into many species. For example, under which type of processors they are oriented - AMD, or Intel. Each of the classes of competing CPUs is unique and requires an individual socket. AMD is: AM1, AM3 +, AM4, FM2, FM2 +. The system boards intended for the CPU from Intel have connectors: LGA 1150, LGA 1151, LGA 2011, LGA 2011-3. Motherboards are divided by the type of supported memory - DRR3 or DDR4.

Nevertheless, the most famous separation of the motherboard on the species is based on the form factor - the parameter is determining the board, as well as the fastening and sockets for the supply of power supply. Main representatives: E-ATX, Micro-ATX, MINI-ITX, MINI-STX, STANDARD-ATX:

Standard-ATX - The most common form factor among users is great, for gaming machines and for the working system. Average dimensions - 305/244 millimeters. It is well compatible with most types of enclosures. A sufficient volumetric area reduces the likelihood of overheating, since the places for the remaining parts are larger and they do not have to be clamped in a limited body, which has a positive effect on the air flow between them. Allows you to set two video cards;
Micro-ATX inferior in size origin (244/244 millimeter). They have less PCI nests. Are mainly suitable for work, but there are samples suitable for games, but their smaller than the previous representative;
Mini-ITX - Some of the most compact motherboards having dimensions of 170/170 millimeters. More suitable as workers and multimedia solutions, because the graphics connector may be absent, therefore, please contact the integrated option. Nests under the RAM modules - one pair;
E-ATX - Excellent solution to gamers. There is an opportunity to install several graphic accelerators at once, and even a pair of CPU can be put on certain models. Average dimensions of 305/272 millimeters. Also, these models can be a good option for the server machine;
Mini-stx - The mini-PC solution is not suitable for games, but it is a completely acceptable option for studying and work. The nests where the graphic accelerator will be installed, and only two nests under RAM. The average size is 140/147 millimeters.

Characteristics of motherboards

As usual, do not forget to affect the issue of the main characteristics of the motherboard. So, let's begin:

Form factor - as already mentioned, this parameter, includes the size, location of the motherboard, as well as connectors for additional devices;
Type of motherboard socket - socket where CPU is installed. An important parameter as we know that the specific type of processors requires a certain connector;
The number of slots and the supported type of RAM - the first indicates the possibility of increasing the amount of RAM, the second - on the speed of its operation;
System bus frequency - directly affects computer performance. The more - the higher the performance of the PC. Naturally, this is not the only factor affecting the speed of the computer, but it is necessary to select the components so that the frequency of the system tire is not less than that of other elements;
Chipset is one of the main items when choosing a motherboard. In a large account, it is from it that the type of processor depends on it, which can be used, memory, support for various periphery, etc.;
The number of PCI slots and PCI Express - the number and ability to connect both video cards and other extension boards using this interface will depend on it;
The number of SATA sockets - will allow you to understand how much HDD, SDD, and optical disk drives can be connected;
The presence and characteristics of integrated: network, graphic and sound cards - will allow you to understand what your PC will be able to do without buying their discrete analogues;
The presence and number of external connectors are both for a stationary computer and a laptop, it is important to have at least 3 USB ports, accessing headphones and inputs for the microphone. In addition, Ethernet port is also necessary, VGA (already old), HDMI. Although here more must be repelled from your own needs.

conclusions

Summing up, we can say that today the motherboard is a complex device that connects between all components of the computer, manages their work, and is also responsible for the number of additionally connected equipment. This board determines the characteristics of your PC and establishes restrictions on its upgrade.

System board (System Board) - the second most important component in. In addition to the term "motherboard", the name "Motherboard" (Motherboard) is used. The main purpose of the motherboard is the connection of all computer nodes into one device, so, by and large, it is just a set of wires between the processor contacts and contacts of memory modules and peripheral devices. All the other elements located on it are minor functions, serve only for junction and matching signals. Of course, some block on the system board can be carried the proud name "controller", but even in this case its purpose is to perform auxiliary functions.

Constructively, the PC motherboard is performed in the form of a multilayer textolite printed circuit board. The composition of the layers can reach 12, but most often used 8 (except for paints and varnish). Between each layer there are printed conductors made of metal foils (the deposition or spraying method can be used), which connect the contact terminals of microcircuits, resistors, capacitors and connectors among themselves. Below is the incision of the Gigabyte system board manufacturing, which suggested increasing the thickness of the copper layers for nutrition and ground up to 70 microns.

As a rule, the thickness of the conductors is two times less, so an increase in the thickness of copper tires improves the cooling of the elements of the system board, but the mass of technological difficulties arises. Since modern processors work with external devices at a frequency of several hundred megahertz, the length and location of printed conductors are now calculated according to the same principles as for microwaves, when each excess centimeter of the conductor plays a huge role.

There is a chipset between the processor, the chapel memory modules and external devices - a set of microcircuits that perform service functions on the distribution of signals between all blocks. When the supply voltage is applied, the chipset generates a specific command sequence that activates the processor. The processor, in turn, the BIOS program tests and activates the remaining devices installed and connected to the system board. If the start of the computer was successful, the chipset chip microcircuits associate the processor, memory and peripheral devices into a single integer - a computing device, ready to execute user commands or to respond to a certain way to appear signals in the interface lines. The flow of information from the processor to RAM and back passes through the electronics of the chipset. Even if there are only buffer chains in the chipset, then they, alas, make a little time delay, even if Ideally, in one system tank. For modern computer systems, such a delay is already a lot, therefore, first AMD Corporation, and then Intel moved the memory controller to the crystal. With this principle of building the processor, the processor works with memory directly, and eliminates unnecessary links, which increases the overall performance of the system. There are other options for building system boards that depend on the processor architecture. For example, the transfer of the interface (for PCI-E) from the chipset on the chains located on the processor crystal is becoming popular with a chain crystal that accelerates the work of the graphics subsystem. In particular, all the controllers of external devices are permissible on the processor crystal, we note that such a scheme is applied since the Intel 80186 processors, but it did not fit in desktop computers.

ATH Form Factor

Whatever enough, the most permanent PC personal computers are a form factor (overall dimensions and location of elements), which, as if relating to each other, new and old models. Due to the fact that all the developers of system boards and peripherals adhere to single rules for fastening boards and location of nodes in the housing, users can independently upgrade their computer by installing the necessary peripheral devices, changing the old processor to a new one, etc. There are two main standard for system fees. - AT and ATH. The first - AT form factor is a computer board with a morally obsolete processor. The second - ATH form factor is a standard, according to which new computers are being developed. The difference between these two standards in the arrangement of the processor and interface connectors, which entails the need to use various buildings. But everything else is fixing the system board to the housing, the location of the slots, etc. - one way or another coincides. As a transitional option between AT and ATH, for example, system fees were produced, which could be installed both into the housing with the AT power supply and in the ATX housing.

Below is the location of the main elements of the personal computer according to the ATX specification, including version 2.2. In particular, one of the main differences of this version of the ATX specification lies in the fact that the system board is derived for the contour, which turned out to be necessary due to the huge size of the cooling system of the modern processor. Please note that in previous versions of the specification, the installation unit was allowed over the processor, but this led to huge problems with the cooling of the processor.

The situation is somewhat more complicated with small-sized and branded computers, which use system fees whose dimensions differ from the standard (other form factors are used, which are based on the ATX form factor). To reduce dimensions, various techniques are used, for example, a decrease in the number of slots for peripheral devices, the use of various adapters in order to be able to arrange peripheral cards not vertically, but horizontally, parallel to the plane of the motherboard. For such systemics and buildings, there is always a problem of modernization, often leading to the fact that it is easier to buy a new computer, rather than deal with the search for suitable elements to the old. Below are the maximum dimensions of the systemics of personal computers that are most common in Russia.

VTX Form Factor

Intel has published in 2004 the Balanced Technology Extended (Balanced Technology Extended), which is the development of ATX standard for new high-performance processors. The main purpose of the specification is to improve the cooling and an increase in the mechanical strength of the motherboard; How it defines the VTX specification. In addition, the specification standardizes methods for connecting to the input / output interface system, housing design. Since the appearance of computers performed according to VTX specifications, implies the development and release of new system boards, then five years later, to some kind of significant industrial release, the case has not yet come. It can be noted that the alteration of the PC motherboard is a great work of developers and engineers, plus a huge amount of product testing, error correction and problems. True, today, when processor developers have finally abandoned the problem of heat dissipation, the introduction of VTX form factor turned out to be not so important as it was necessary for the latest versions of Intel Pentium 4 processors and for a number of quad-core Intel and AMD processors.

Sockets

The decade of decades has been released many of the most diverse processors intended for use in PC personal computers. Some types of processors turned out to be so successful that they were produced for a wide variety of applications, for example, to install in laptops and industrial devices. When the type of processor or its purpose is changed, the silicon crystal with millions of transistors was mounted in a new case having other dimensions and methods for fastening to the system board. Unfortunately, the main pathway of modern microelectronics goes towards an increase in the number of contacts that the processor housing is supplied. Naturally, when changing the number of contacts, the design of the processor connector is changed, which is installed on the system board. If the source of current processors had only 16 contacts and was installed in a very simple connector - the "crib", then the models of modern processors overcame the line of a thousand contacts. The connector for installing modern processors is called socket (Socket). It is also called a zero-zif-zif-zero insertion force (ZIF-Zero Insertion Force), and the marking numbers starting with the Socket 370 model, they say the number of contacts. In the recent past, the most popular connector for installing processors was Socket 7, designed for Pentium processors, and Socket 370, in which the Pentium III processors were installed. It can be noted that the Socket 7 was permissible to install both Intel processors and AMD Corporation Processors. For some time, processors mounted on printed circuit boards, which were intended to be installed in special slots resembling slots for memory modules. For Intel Corporation Processors, such a connector was called Slot 1, and for AMD - Slot A. The earliest models of Pentium 4 processors were designed for installation in Socket 423. In the future, Socket 478 began to be used for Pentium 4 processors (MPGA478)

Intel Core 2 processors and the latest versions of Pentium 4 are manufactured with flat conclusions ("Fleet") and are installed in the socket LGA 775 connector.

In the new Intel Core i7 processors released at the end of 2008, the same design of the conclusions of the processor and socket are used, only the number of contacts is significantly increased, and the name of the LGA 1366 socket is proposed. In 2009, the LGA 1156 socket for Intel Core i5 processors was proposed.

The Athlon processors are installed in Socket 462, it is Socket A. for Opteron and Athlon 64 processors, Socket 940 has been developed (and its modernization of Socket 939), and the first Athlon 64 processors were produced for Socket 754 (processors for this socket continues until now). Socket 940 and AM2, to clarify a socket mounted on a system board, it is better to look at the inscription on the plastic socket case.

The motherboard is the main mounting part to which internal components and external, peripheral devices are connected. It is a basic element of any desktop, portable, tablet or pocket computer. This publication will consider the motherboard device, as well as the purpose of its main components.

The motherboard ensures the interaction of various PC devices. Its mandatory elements are connector or Socket processor (CPU), chip set, connector for memory modules. In addition, mandatory PC elements are: BIOS microcircuit, controllers, various power connectors, connectors connecting elements and computer devices.

BIOS is a chip, with defined test and bootable programs for the CPU, because at the initial stage, the processor does not yet know how to work with all devices located in the PC. This chip is located in close proximity to the CPU and isolate from a separate battery - "Tablets", located on the board, next to the expansion slots.

Initial testing occurs without processor. Only after checking the electronic components of the computer for the absence of short circuit, and the correspondence of currents in the BP, the BIOS "allows" to supply the power supply unit to the fee and processor.
After, the CPU reads with the BIOS a certain algorithm of actions, due to which the performance of all components of the PC occurs. If everything is in order, then the operating system is launched on "Winchester". After that, all PC control is transmitted exclusively by the operating system.

Thanks to its work, the BIOS imperceptibly performs one of the most important functions in the computer.

Central processor connector

The connector or socket processor, on the motherboard the largest. The CP connectors models differ in appearance, location and number of contacts. Depending on the processor model, they are two types:

Single, from ang. "nest". It is a rectangular or square connector with a plurality of holes, located along its perimeter. The processor is mounted in such a connector - horizontally.
The slot connector (from English. "Glug") is a long series of contacts located in a plastic case. It is intended for vertical installation of the CPU. To date, this type of connectors is practically not used.

Appointment and design features of the chipset

The motherboard chipset is usually two different chips, called the Northern and South Bridge. They received their names exclusively from the location: the North Bridge is located near the CPU, and the Southern - below, near the video card connector and the expansion slots. They are an essential link between the hardware and the PC processor. In some modern system board models, a chipset consisting of one microcircuit can be used. This is due to the design features of the processor that has taken on the functions of the southern bridge.

The North Bridge communicates the CPU with the fastest components of the PC and with the southern bridge. Due to the high load, the bridge is very hot, therefore, most often, it is equipped with a radiator for better cooling.

The North Bridge is associated with a high-speed CPU. The most modern, today, is the QPI bus, from Intel.
To communicate the bridge with the video adapter, the AGP 3.0 bus can be used, or PCI EXPRESS 3.0, the mass release has begun since 2012.
Bridge chips among themselves one of the presented interfaces: PCI, Hub Link, Dmi or Hypertransport.

The southern part of the chipset, coordinates the work of slower components of the PC, and also provides data transfer from these components to the northern chip.

The south bridge consists of controllers: for communication with the northern part of the chipset, extension boards, peripheral devices and components, hard disks and other slow devices

The most common interfaces, in modern PCs are considered: USB 2.0 - 3.0; Wi-Fi and Ethernet. For the connection of the southern bridge with hard disks, PCI tires are used, as well as more modern tires with SATA and SCSI and SAS. To match the work of the bridge with the BIOS, the LPS bus with a clock frequency of 33.3 MHz is most often used.

Memory Module Connectors and Other Extension Boards

In any computer, there is a temporary information storage referred to as RAM. It is a module with several chips on board, which is mounted in special connectors, so-called slots. As a rule, they are located next to the processor and the northern part of the chipset. Slots of memory modules are equipped with locks that are made with protection from improper installation. The amount varies from 2 to 6, depending on the value of the "motherboard" and its form factor.

An important component of the motherboard is the PCI-Express slot, to connect a discrete video adapter, without which the image is not possible to the monitor (unless the integrated video card) is noted.

In addition to the above slots, pin connectors are located on the board to connect hard disk data tires. Previously, for this was used the IDE interface. On modern PCs, the SATA interface is most often used.

On any "motherboard" there are no compulsory ports to connect additional peripheral devices. As a rule, the main set includes: fan power connectors and buttons located on the system unit panel; LEDs that signal "Winchester" and power supply. In addition, on the back of the board is: several USB ports; LAN connector for connecting a cable to a network card; Connectors of the audio input and exit; HDMI connector, etc. In most models, you can encounter PS / 2 keyboard connections and manipulator.

To power the motherboard, as well as all electronic and mechanical components, it has 20 or 24 pin connector on which the voltage from the power supply is located in the PC housing.

Not sure about choosing a model MP -! We will select the optimal model.

Types of motherboard

Forms The motherboard factor is a specific standard, thanks to which the size of the system board is determined, its fastening method in the PC housing, the presence and location of the ports and interfaces of the tires, as well as the CPU connectors and RAM.

Currently, there are several formative form factors:

ATX is the largest motherboard largest, which has a lot of slots and the convenient location of the water-output ports.
EATX is a system fee no different from ATX, except for sizes that make up 30.5 cm. X33 cm.
MicroAtx is the reduced version of the ATX motherboard. It was designed for PC, which does not require a change in configuration, so it has 4 expansion slots. As a rule, such boards are equipped with 24 power connector and have dimensions, 24, 5 cm. X 24.5 cm.
BTX - motherboard designed to create small system units. Nevertheless, it has 7 expansion slots in size 26.7 x 32.5 cm.
Micro BTX is a reduced copy of the "motherboard" VTX, which has 4 expansion slots and dimensions 26.7 x 26.4 cm.
Miniitx is the smallest, from modern computerkets for the computer. Its dimensions are 17 cm by 17 cm.
SSIEEB and SSIESEB. Motherboards of these form factors are applied to create servers. Dimensions are: 30.5 x 33.0 cm. And, respectively, 30.5 x 25.9 cm.

If you decide to gather a PC, we recommend using the motherboard for this, ATX factor. A lot of free space and capabilities for changing the configuration will allow you to fully enjoy the assembly and use of your home PC.

Systemic (Master) fee - a printed circuit board at which most components of the computer system are installed. The name comes from the English Motherboard, sometimes the MB reduction is used or the word MainBoard is the main board.

Components of motherboard

Modern personal computers have a bus architecture. Directly on the motherboard is only a minimum set of microcircuits, and all other are combined with the system tire. This uses special extension boards and connectors (slots). Thus, the motherboard is usually located:

sound card

Hard drive controllers

To connect hard disks with the PATA interface, a 40-wire cable is usually used (also referred to as a loop). Each loop usually has two or three connectors, one of which connects to the controller connector on the motherboard (in older computers, this controller was located on a separate extension board), and one or two other others are connected to the discs. At one point in time, the P-ATA loop transmits 16 data bits. Sometimes there are IDE loops that allow you to connect three drives to one IDE to the channel, but in this case one of the disks works in READ-only mode.

SATA (Serial ATA) is a serial interface of data exchange with information drives (usually with hard drives). SATA is the development of the ATA (IDE) interface, which after the appearance of SATA has been renamed PATA (Parallel ATA).

SATA / 150. Initially, the SATA standard provided for the operation of the tire at a frequency of 1.5 GHz, providing bandwidth of approximately 1.2 Gb / s (150 MB / s). (20% performance loss is explained by using the 8B / 10B coding system, at which every 8 bits of useful information accounts for 2 official bits). SATA / 150 bandwidth is slightly higher than ULTRA ATA tire bandwidth (UDMA / 133). The main advantage of SATA in front of the PATA is the use of a sequential tire instead of parallel.

SATA / 300, operating at a frequency of 3 GHz and providing bandwidth up to 2.4 Gbit / s (300 MB / s) for the first time, was first implemented in the NFORCE 4 chipset controller. NVIDIA. Very often, the SATA / 300 standard is called SATA II. Theoretically SATA / 150 and SATA / 300 devices must be compatible (both SATA / 300 controller and SATA / 150 device and SATA / 150 controller and SATA / 300 device), however, for some devices and controllers, manual setting of operation mode is required (for example , SEAGATE supporting SATA / 300 supports SATA / 150 comprising SATA / 150 forced jumper). The SATA standard provides for the possibility of increasing the speed of operation up to 600MB / C (6 GHz).

Symbols of system plats

There are many types of system boards. Typically, the type of system board is determined by the base microprocessor, a sizer (form factor), a chipset, a set of slots for RAM and expansion cards, the BIOS program, etc. Consider these features ...

Basic microprocessor, processor connectors and frequency

Motherboard Form Form - Standard defining the size of the motherboard for a personal computer, the place of its attachment to the housing; Location On it Tire Interfaces, I / O ports, a central processor socket (if any) and slots for RAM, as well as the connection type for connecting the power supply. The form factor (like any other standards) is a recommendatory nature, but the overwhelming majority of manufacturers prefer to observe it, since the cost of compliance with existing standards is the compatibility of motherboard and standardized equipment (periphery, expansion cards) of other manufacturers.

Outdated: Baby-AT; Mini-ATX; Full-size AT board; LPX. Modern are considered: ATX; microatx; Flex-Ahh; NLX; WTX. Implemented are considered: mini-ITX and NANO-ITX; BTX, Microbtx and Picobtx There are motherboards inappropriate any of the existing form factors (see table). This is usually due to either the fact that the computer produced is highly specialized, or the desire for the manufacturer of the motherboard independently produce and the peripheral devices to it, or the impossibility of using standard components (the so-called "brand", for example Apple Computer, Commodore, Silicon Graphics, Hewlett Packard, Compaq more often Others ignored the standards; In addition, in the current form, the distributed production market was formed only by 1987, when many manufacturers have already created their own platforms).

Chipset - A chipset (maybe in one chip), which is an interface between the components of the computer, such as CPU, RAM, ROM, I / O ports.

A set of interfacral circuits, as a rule, consists of three main: Northern Bridge (provides interaction between CPU and memory, AGP IT bus), southern bridge (provides interaction between CPU and hard disk controller, PCI tires, USB IT.D.) , Super I \\ O (responsible for the COM, LPT, PS / 2 ports).

North Bridge - It is one of the main elements of the computer chipset and is responsible for working with the processor, memory and video adapter. The northern bridge defines the system tire frequency, a possible type of RAM (SDRAM, DDR, OTHER), its maximum volume and the rate of information exchange with the processor. In addition, the north bridge depends on the presence of a video adapter tire, its type and speed. For computer systems of the lower price level in the north bridge, the graphic core is often embedded. In many cases, it is the northern bridge that defines the type and speed of the system expansion of the system (PCI, PCI Experess, the other). The North Bridge is one of the main elements of the computer chipset and is responsible for working with the processor, memory and video adapter. The northern bridge defines the system tire frequency, a possible type of RAM (SDRAM, DDR, OTHER), its maximum volume and the rate of information exchange with the processor. In addition, the north bridge depends on the presence of a video adapter tire, its type and speed. For computer systems of the lower price level in the north bridge, the graphic core is often embedded. In many cases, it is the northern bridge that defines the type and speed of the system expansion of the system (PCI, PCI Experess, the other).

South Bridge Microcircuit (South Bridge) With built-in tools and external elements, controls the operation of a large number of relatively slow peripheral devices.

RAM (RAM - operational storage device) - In computer science - memory intended for temporary storage of data and commands required by the processor to fulfill their operations. RAM transmits the command processor and data directly or through the cache memory. Each variable memory cell has its own individual address.

In modern computing devices, the RAM is a storage device with arbitrary access (RAM) and can be manufactured as a separate unit, or may be included in the design of a single-chip compartment.

Types of RAM:

SIMM (Eng. Single In-Line Memory Module) - Memory modules widely used in computer systems in the 1990s. There were several modifications, among which three were most common. With the advent of Pentium, due to the low performance of the dynamic memory of the SIMM modules, their specification has undergone changes, as a result of which newer modules (they called EDO) became incompatible with old (FPM), possessing a little greater speed. Pentium boards, as a rule, supported both types of memory, while most 486 cars supported only old (FPM) type. It was impossible to distinguish them in appearance of them and only the "scientific tyk method" helped determine their type. Installing the "wrong" type of memory did not lead to faults - the system simply did not see the memory. Since 72-pin modules have already needed 72-pin modules on Pentium boards with a 64-bit data bus, gradually and in pairs "combined", resulting in the appearance of the first DIMM modules.

DDR SDRAM (from English. "Double Data Rate Synchronous Dynamic Random Access Memory" - double-to-rate synchronous memory data rate with arbitrary access) - This is the type of RAM used in computers. When using DDR SDRAM, a large bandwidth is achieved than in an ordinary SDRAM, due to data transmission on both fronts of the signal. Due to this, the data transfer rate is actually almost doubled without increasing the frequency of the memory bus. Thus, when working DDR at a frequency of 100 MHz, we obtain an effective frequency of 200 MHz (when compared with an analog SDR SDRAM). In the JEDEC specification there is a note that to use the term "MHz" in DDR incorrectly, correctly indicate the speed of "millions of transmissions per second through one data output".

DDR2 SDRAM (from English Double-Data-Rate Two Synchronous Dynamic Random Access Memory - Double-to-date synchronous memory data rate with arbitrary access) - This is the type of RAM used in computers. Like DDR SDRAM DDR2 SDRAM uses data transmission on both fronts of the clock signal, due to which the memory bus frequency as in the conventional SDRAM can actually double the data transfer rate (for example, during the operation of DDR and DDR2 at 100 MHz, the effective frequency is obtained 200 MHz). The main difference between DDR2 from DDR is the ability to work on a much greasy clock frequency, thanks to the improvements in the design. But the modified data component of the pre-election buffer, which allows to achieve high clock frequencies, at the same time increases the delays (Latency) when working with memory.

Expansion card slots:

ISA (from English Industry Standart Architecture, ISA BUS) - 8 or 16-digit system bus IBM PC-compatible computers. Used to connect the ISA standard expansion boards. Structurally performed in the form of a 62 or 98-pin connector on the motherboard. With the advent of ATX motherboards, the ISA bus has ceased to be widely used in computers. But while it can still be found in old AT computers, as well as in industrial computers. For embedded systems, there is an ISA bus layout option, characterized by the connector applicable - PC / 104 bus.

PCI (English Peripheral Component InterConnect, literally: interconnection of peripheral components) - Today De Facto Standard System Bus for connecting peripheral devices to the computer's motherboard. The standard on the PCI bus determines:

physical parameters (for example, connectors and wiring of signal lines);

electrical parameters (for example, voltages);

logical model (for example, tire cycle types, addressing on the tire);

The development of the PCI standard is engaged in the PCI Special Interest Group.

AGP (from Eng. Accelerated Graphics Port, Express Graphic Port) - Developed in 1997 by Intel, a specialized 32-bit system tire for a video card. Appeared simultaneously with the chipsets for the Intel Pentium II processor. The main task of the developers was an increase in productivity and reducing the cost of the video card, due to a decrease in the number of built-in video memory. According to Intel, large volumes of video memory for AGP cards would not be needed, since the technology provided high-speed access to the overall memory.

PCI EXPRESS or PCIE or PCI-E (also known as 3gio for 3rd Generation I / O; not to be confused with PCI-X or PXI) - Computer bus using a PCI bus software model and a high-performance physical protocol based on sequential data transmission.

BIOS (English Basic Input-Output System - Basic I / O System, BSVB) - A program located in the ROM (constant storage device) of a personal computer and executed when the power is turned on. The main feature of the BIOS is to prepare a machine to ensure that the main software (in most cases is an operating system) recorded on various media (hard disk, a floppy disk or a CD, available via the network), could boot and gain control over the computer. The designation of such a basic term BIOS is inherent in personal computers based on processors with the X86 architecture. For computers based on other types of processors, other terms are used to indicate such functions: for example, the basic machines with the SPARC architecture processor is called Prom. BIOS performs self-test (post) devices, then searches for the operating system bootloader (Boot Loader) on available disks. If the bootloader is not found, the BIOS gives an error message. Many old personal computers that did not have a full-fledged operating system, or its download was not necessary to the user, called the built-in interpreter of the Baysik language. Also, the BIOS also contains a minimum set of service functions, for example, to display messages to the screen or reception of characters from the keyboard, which causes the decryption of its name: Basic Input-Output System is the basic I / O system. In modern personal computers, the BIOS also provides an interface for low-level configuration of the system components, and also allows you to load the operating system through the interfaces, initially not intended for this, including USB and IEEE 1394. Also boot over the network (applied to "thin clients "). In some BIOS, "AH is released additional functionality (for example, playback of DVDs), support for the built-in working environment (for example, a BASIC language interpreter).

The motherboard is the basis of the computer. It contains the main electronic elements: processor, memory, BIOS, microcircuit, etc.

Types of system plat

All-in-One - the board on which the elements necessary for the computer are posted. Motherboard - a board containing basic nodes and expansion connectors for installing childboards.

Motherboard composition

On the motherboard are located:

1. Sets of large single-chip electronic chips - chips (central processor, other processors, integrated device controllers and their interfaces)

2. RAM microcircuits and their boards connectors

3. Electroches electronic logic

4. Simple radio elements (transistors, condensers, resistance, etc.)

5. System bus connectors (ISA, EISA, VESA, PCI, etc.) connectors.

6. Slots for connecting extension boards (video cards or video adapters, sound cards, network cards, IDE, EIDE, SCSI peripheral devices interfaces ...)

7. I / O port connectors (COM, LPT)

general characteristics

The motherboard is designed to place or connect all the other internal computer devices - serves as a kind of platform, on the basis of which the configuration of the entire system is built.

The type and characteristics of various elements and motherboard devices are usually determined by the type and architecture of the CPU (motherboards based on processors in Intel, AMD, Cyrix, etc. - 8086/8088/80188, 286, 386, 486/586/686 , Pentium, Pentium II-V. As a rule, it is the central processor or processor, their family, type, architecture and execution determine one or another version of the architectural performance of the motherboard.

According to the number of processors that make up the central processor, distinguish between single-processor and multiprocessor (multiprocessor) motherboards. Most personal computers are single-processor systems and are equipped with single-processor motherboards.

Setting the motherboard on specific electronic components is carried out using jumpers (Jumpers). In particular, these jumpers settings are set to a specific processor model - the clock frequency and supply voltage are adjusted.

The motherboard is attached to the chassis of the system unit body, as a rule, two screws with insulating plastic mounts.

Modern requirements for motherboards

Modern motherboards meet the requirements of the Energy Star program. This is an energy-saving program introduced by the American Environmental Agency (EPA - Environment Protection Agency). According to these requirements, the fee is referred to the category of "green" (Green Motherboard), if its power consumption in idle mode is not more than 30 W, toxic materials are not used in it, 100% disposal is allowed after the expiration of the service life.

Consider the device of the typical Pentium-class motherboard with a 430HX chipset (ASUS P55T2P4).

1 - USB connector (USB Header), 2 - installation hole, 3 - Keyboard controller (Keyboard Controller), 4 - BIOS microcircuit (Flash BIOS ROM), 5 - ISA Tire Connector (ISA BUS Slot), 6 - PCI bus connector (PCI BUS Slot), 7 - Multimedia expansion connector (Mediabus Slot), 8 - installation hole, 9 - clock chip with the power element (Real-Time Clock / CMOS), 10 - processor connector (CPU Socket),

11 - voltage regulator, 12 - connectors connecting the case indicators,

13 - condensers, 14 - antistatic coating, 15 - Switches (Jumpers),

16 - 2-level cache microcircuits (Cache Chips), 17 - Cache-memory expansion connector, 18 - TAG-Memory Expansion Connector (Tag Ram Expansion Socket), 19 - Intel 430 HX chipset (Chipset Chips), 20 - Memory module connectors (SIMM Sockets), 21 - Drive connector (Floppy Header), 22 - Speaking of the first IDE device (Primary Ide Header), 23 - Second IDE device connector (Secondary IDE Header), 24 - Power Connector (Power Connector), 25 - I / O controller (I / O Controller), 26 - parallel port connector (LPT HEADER), 27 - Connector 1 Serial Port (COM1 Header), 28 - 2 serial port connector (COM2 Header), 29 - PS2 port connector (PS2 Mouse Header), 30 - Keyboard Connector (Keyboard Connector)