What is included in the computer system unit. The structure of the system unit - which components are responsible for the operation of the computer

Personal computer is complex electronic device, designed to perform a wide range of tasks. This could be various calculations, calculations, listening to music, watching videos, various office tasks, games and much more.

Personal computer can be stationary or mobile. TO mobile computers include laptops, netbooks and tablets.

A desktop computer is also lately has undergone changes, but in most cases it represents the system unit, monitor, input devices (keyboard and mouse), audio devices (speakers, headphones and microphone), as well as other peripheral devices (printer, scanner, etc.).

For the normal functioning of a personal computer, you only need a system unit, a monitor, a keyboard and a mouse.

An operating system is also required, in most cases they use Windows, but you can also download Linux.
Next we will take a closer look at each of these devices.

System unit

Main node personal computer is the system unit. It is a case, most often a metal vertical box, on the front panel of which there are power buttons and disk drives. All the necessary connectors and cables are located on the back wall. The system unit consists of a power supply, a motherboard (also known as a motherboard or “motherboard”), hard drive(HDD), video card, processor (CPU), RAM(RAM), disk drives (CD/DVD), sound card and network card. Often the network and sound cards are integrated into motherboard, that is, the radio elements of the board are soldered directly to the motherboard.

power unit

The power supply is made in the form of a separate box, which is located at the top back of the system unit and has several power cables for all elements of the system unit.

power unit

Motherboard

The motherboard is the largest in system unit printed circuit board, on which all the main components of the computer are installed (CPU, RAM, video card), it also has connectors for connecting hard disk and drives, as well as cables of USB ports and connectors going to back panel housings. The motherboard coordinates the operation of all computer devices.

Motherboard

CPU

The processor is a chip designed to perform basic computing operations. Processors are produced by two companies: AMD and Intel. Depending on the manufacturer of the processor, the connector (location of its installation) also differs, so when choosing a motherboard you should not forget this. You simply won't fit an AMD processor into an Intel motherboard.

CPU

Video card

The video card is a separate printed circuit board installed in the connector PCI Express motherboard and is designed to display images on the monitor screen. It processes the received information and converts it into analog and digital video signals, which are supplied to the monitor via a cable connector. A video card usually contains a processor (GPU) and RAM.

Video card

RAM

RAM is one or more small cards installed in special sockets on the motherboard (DDR). RAM provides temporary storage of intermediate data while the computer is running. RAM is characterized by access speed and memory capacity. To date, the most fast memory has DDR3 standard.

RAM

Hard drive

The hard drive is a permanent storage of data; it can be either user data, system data or temporary data. The hard drive stores the operating system, without which normal operation computer will be impossible. The operating system can also use hard drive to save the contents of RAM (for example, in hibernation mode). It is a closed metal parallelepiped hard drive that is connected to the motherboard via a connector (SATA).

Hard drive

Drive

Drive optical disks It looks like a hard drive, but has a retractable tray on the front panel for installing optical drives. Serves as a drive for reading and writing optical discs.

Others can be installed on the system board additional devices, For example Wi-Fi module or TV tuner.

Monitor

The computer monitor is used to graphical representation information that is certainly understandable to the PC user. Recently, exclusively liquid crystal displays (LCDs) have been produced. Monitors can be equipped with digital and/or analog video connectors (DVI, HDMI).

Keyboard

The keyboard is an integral input device of any computer. The keyboard consists of groups of keys for entering symbolic information. Also, many modern keyboards are equipped additional keys, for example, to control media players and various programs.

Hi all. Alexander Osipov is in touch. Today we will talk about the main components of a personal computer.

The computer structure has undergone virtually no changes over the entire period of their existence. We all also hide the main computer devices in the case. Only the computer components themselves change, but not their purpose. They are becoming more technologically advanced, more reliable, more spacious and faster. New types of connectors for devices and methods of connecting them are being invented and put into practice.

In this article I will tell you and clearly show the device modern computer. Although the topic is quite hackneyed, to say the least, I also really wanted to speak on this topic, since many people do not know, or have an erroneous idea, what a system unit, processor, video card, etc. are.

Some call the system unit a processor, others confuse the hard drive with RAM. This ignorance is very successfully used unscrupulous sellers computer stores. After all, if you cannot distinguish one computer device from another, then it is easy to deceive you. So first, let's do a little computer education.

A computer system unit is a computer case with components installed inside it, and nothing more. I say this to those who call the computer system unit a processor or something else.

To understand whether you are being deceived or not, you need to learn to figure it out yourself and choose the right ones. computer devices and the components you need.

Let's move on to brief description necessary computer devices for its full operation.

(on computer slang may be called a system unit, case) - a device whose main purpose is to protect from external influence And mechanical damage the main components of the computer, it is most convenient to place and support the necessary temperature regime for their smooth and long-term operation.

It also allows you to shield electromagnetic radiation.

There are many modifications of computer cases, differing in size and material. You can read more about computer cases in the article.

Motherboard (system) board

(motherboard, mainboard, MB, in slang mother, mother, motherboard). It is also called system board, since it is she who unites and organizes the work of all computer nodes. This is where we insert CPU, RAM, video card. Its connectors are connected hard drives, optical drives and various peripheral devices.

To control and monitor the operation of all devices, the motherboard has many different chipsets, microcircuits and controllers.

The choice of motherboard model determines what type and from which manufacturer (Intel, AMD) the processor will be installed in your computer.

Also, when choosing a motherboard, pay attention to the type of memory it uses (DDR2, DDR3) and the type of connector (AGP, PCI-E) for the video card (if necessary).

If you buy additional devices that connect inside the system unit (sound card, video card, modem, TV tuner), then carefully look to see if you have any for them free seats and whether the connectors on the motherboard are suitable for the equipment you have chosen.

When upgrading or buying a new computer, first of all decide on the type and model of the processor, then choose a motherboard for it and only then the rest necessary devices compatible with your motherboard.

Central CPU

(CPU from the English central processing unit, CPU, CPU central processing unit). Represents integrated circuit executing machine instructions. Main part hardware computer. It is the processor that processes the lion's share of the data with which We load the computer.

The performance of the computer as a whole greatly depends on the speed of the central processor.

Today, CPU performance is determined by the clock speed and the number of cores. There are other processor parameters that affect its performance, but I will describe them in a separate article.

Now on the microprocessor market, both for desktop computers, and laptops are led by two main manufacturers. These are Intel and AMD corporations.

RAM

RAM(random access memory from the English. Random Access Memory; in computer slang - memory, RAM).

It is a non-volatile set of chips in which data and commands are temporarily stored, which are subsequently used by the central processor to perform specified operations.
Typically, RAM contains the necessary data for work operating system And running processes various programs.

The volume and speed of RAM determine the number of tasks that a computer can simultaneously perform and the speed of their execution.

Hard drive (hard drive, HDD)

Hard drive or drive on hard magnetic HDD drives (HDD from Hard disk drive, hard drive) is a random access information storage device based on the principle of magnetic data recording.

Today, this is the main data storage device on all desktop computers and many laptop models.

This market segment for a long time remained motionless. Only the volume of information stored on the hard drive increased, but not its speed.

Now HDDs are being replaced by SSD (solid-state drive) hard drives based on flash memory. Their operating speed is many times higher, but the price is still high.

Hard drive capacity is measured in Gigabytes or Terabytes.

The larger the hard drive capacity, the more different data you can store on your computer.

The hard disk drive is the biggest bottleneck in the speed of a modern computer.

Video card (graphics accelerator)

(graphics accelerator, video accelerator, video adapter, graphics card or card) is a special electronic device that processes and converts the data received by it for further output on the monitor screen.

All modern video cards have their own GPU(allows you to seriously relieve the central processor), which, depending on the architecture, is capable of processing graphic information in 2D or 3D modes.

Video cards are divided into external(faster) and built-in(in the form of a separate chip) into the motherboard (slower ones).

Modern 3D games will require a fairly powerful external video card, and to work in office applications, watching movies or simple games, the built-in video adapter is enough.
Recently, processors with built-in graphics core. I will tell you what this gives in one of the articles.

Optical drive (CD, DVD-RW)

– mechanical device, controlled electronic circuit and designed for reading, writing or erasing information using lasers of various lengths, with optical media information (CD) such as: CD, CD-R, CD-RW, DVD, DVD-R, DVD-RW, BD-R, BD-RW.
Can work with both single-layer and multi-layer 12cm or 8cm discs.

Computer power supply (PSU)

Computer power supply (PSU)- a very important element computer system. It is responsible for the stability and quality of the power supplied to your other system unit devices.
The reliability and safety of information on hard drives, as well as the long-term existence of other components in the event of a power failure.

Since the network uses AC, and the computer requires a constant one, then the main task of the power supply is its conversion (rectification).

The main characteristics of the power supply are:

• Power (measured in watts)

• Efficiency (Coefficient of Efficiency)

• Built-in surge protection systems

• Cooling

• Dimensions

Also when choosing computer unit supply should be addressed to the manufacturer's name. Brand or noname.

Here you choose, as they say, “with your wallet,” but right choice obvious.

(audio card, “sound card”, sound card) - additional or built-in equipment that allows you to reproduce sound using speaker systems (speakers), as well as process and record it using special software.

At the time of the advent of multimedia computers, sound cards were separate expansion cards inserted into a special slot.

Modern sound cards exist both external and built into the motherboard.
External audio cards provide a significantly more capable processing and output device high-quality sound compared to built-in sound cards.

Floppy disk drive (FDD)

It makes no sense to consider a disk drive for reading soft magnetic disks (floppy disk drive), since it is obsolete, although many still use it.

It was replaced by flash drives, and in place of FDD, in computer case you can insert others necessary devices, type card reader (device for reading various cards memory) or something else.
There are devices on sale that combine FDD and Card reader. There are also floppy drives that connect via USB.

Cooling system

High quality and correct organized system cooling the “hottest” components and the system unit as a whole will prevent many glitches and breakdowns of your computer. From the article you will learn about all the subtleties and nuances of this important element, used in the construction of cooling systems, like a computer fan.

I hope this article will help you in solving the issues and tasks that you face.

There will be a separate article for each of the devices described here, with detailed analysis all the nuances. From the correct purchase to installation in the computer and configuration. Goodbye everyone.

So, what does our ordinary personal computer (PC) that we use at home or at work consist of?

Let's look at its hardware (“hardware”):

• system unit (that large box that stands on your table or under the table, on the side of it, etc.). It contains all the main components of the computer.
• peripherals(such as a monitor, keyboard, mouse, modem, scanner, etc.).

The system unit in a computer is the “main” unit. If you carefully unscrew the screws from its back wall, remove sidebar and look inside, then only at first glance its structure will seem complicated. Now I will briefly describe its structure, and then I will describe the main elements in the most understandable language.

The system unit contains the following elements (not necessarily all at once):

- Power unit

— Hard drive magnetic disk(HDD)

— Floppy disk drive (FDD)

— CD or DVD drive (CD/DVD ROM)

— Connectors for additional devices (ports) on the rear (sometimes also on the front) panel, etc.

— System board(it is more often called maternal), which, in turn, contains:

• microprocessor;
• math coprocessor;
• clock generator;
• memory chips(RAM, ROM, cache memory, CMOS memory)
• controllers (adapters) of devices: keyboards, disks, etc.
• sound, video and network cards ;
• timer, etc.

All of them are connected to the motherboard using connectors (slots). Its elements, highlighted in bold, we will look at below.

And now, in order, about the system unit:

1. Everything is clear with the power supply: it powers the computer. I’ll just say that the higher its power rating, the cooler it is.

2. A hard disk drive (HDD - hard disk drive) is popularly called a hard drive.

This nickname arose from the slang name for the first models of hard disk with a capacity of 16 KB (IBM, 1973), which had 30 tracks of 30 sectors, which coincidentally coincided with the “30/30” caliber of the famous Winchester hunting rifle. The capacity of this drive is usually measured in gigabytes: from 20 GB (on old computers) to several Terrabytes (1 TB = 1024 GB). The most common hard drive capacity is 250-500 GB. The speed of operations depends on the rotation speed (5400-10000 rpm). Depending on the type of connection between the hard drive and motherboard distinguish between ATA and IDE.

3. Floppy Disk Drive (FDD) floppy disk drive) is nothing more than floppy disk drive. Their standard capacity is 1.44 MB with a diameter of 3.5" (89 mm). As a storage medium, magnetic disks use magnetic materials with special properties that make it possible to record two magnetic states, each of which is assigned a corresponding binary digits: 0 and 1.

4 . Drives on optical disks(CD-ROM) come in different diameters (3.5" and 5.25") and capacities. The most common of them are with a capacity of 700 MB. It happens that CD discs can be used for recording only once (then they are called R), and it is more profitable to use repeatedly rewritable RW discs.

DVD originally stood for Digital Video Disk. Despite the name, DVDs can record anything from music to data. Therefore, recently another decoding of this name has become increasingly common - Digital Versatile Disk, loosely translated meaning “digital universal disk" The main difference between DVDs and CDs is the amount of information that can be recorded on such media. From 4.7 to 13, and even up to 17 Gb can be recorded on a DVD disc. This is achieved in several ways. Firstly, to read DVDs, a laser with a shorter wavelength is used than to read CDs, which has significantly increased the recording density. Secondly, the standard provides for so-called double-layer discs, in which on one side the data is recorded in two layers, while one layer is translucent, and the second layer is read “through” the first. This made it possible to write data to both sides of DVDs, thereby doubling their capacity, which is sometimes done.

5. Other additional devices can be connected to a personal computer ( mouse, printer, scanner and other). The connection is made through ports - special connectors on the rear panel.

There are parallel (LPT), serial (COM) and universal serial (USB) ports. By serial port information is transmitted bit by bit (slower) over a small number of wires. A mouse and modem are connected to the serial port. By parallel port information is transmitted simultaneously over a large number wires corresponding to the number of digits. A printer and an external hard drive are connected to the parallel port. The USB port is used to connect a wide range of peripheral devices- from mouse to printer. Data exchange between computers is also possible.

6. The main computer devices (processor, RAM, etc.) are located on motherboard.

Microprocessor (simpler - processor) is the central unit of a PC, designed to control the operation of all units of the machine and to perform arithmetic and logical operations over information.

Its main characteristics are the bit depth (the higher it is, the higher the computer’s performance) and clock frequency (largely determines the speed of the computer). Clock frequency indicates how many elementary operations (cycles) the processor performs in one second.
Processors are respected in the market Intel Pentium and its economy version Celeron, and also appreciate their competitors - AMD Athlon with economy version Duron. Intel processors characterized by high operational reliability, low heat generation and compatibility with all software and hardware. And AMD show higher speed works with graphics and games, but is less reliable.

Computer memory can be internal or external. To devices external memory include the already discussed HDD, FDD, CD-ROM, DVD-ROM. TO internal memory includes permanent storage (ROM, ROM), operational storage (RAM, RAM), cache.

ROM is designed to store permanent program and reference information(BIOS - Basic Input-Output System - basic system input/output).

RAM is fast and is used by the processor for short-term storage of information while the computer is running.

When the power source is turned off, the information in RAM is not saved. For the normal functioning of a computer these days, it is advisable to have from 1 GB to 3 GB of RAM.

Cache memory is an ultra-high-speed intermediate memory.

CMOS memory - CMOS RAM (Complementary Metall-Oxide Semiconductor RAM). It stores computer configuration settings that are checked every time the system is turned on. To change computer configuration settings, the BIOS contains a computer configuration program - SETUP.

Sound, video and network cards can be either built into the motherboard or external. External boards You can always replace it, whereas if the built-in video card fails, you will have to replace the entire motherboard. From video cards I trust ATI Radeon and Nvidia. The higher the video card memory, the better.

Peripherals

The computer consists of 6 groups of keys:

• Alphanumeric;
• Controls (Enter, Backspace, Ctrl, Alt, Shift, Tab, Esc, Caps Lock, Num Lock, Scroll Lock,Pause, Print Screen);
• Functional (F1-F12);
• Numeric keypad;
• Cursor controls (->,<-, Page Up, Page Down, Home, End, Delete, Insert);
• Function indicator lights (Caps Lock, Num Lock, Scroll Lock).

Mouse (mechanical, optical). Most programs use two of the three mouse keys. The left key is the main one, it controls the computer. It plays the role of the Enter key. The functions of the right key vary depending on the program. In the middle there is a scroll wheel, which you quickly get used to.

Modem - network adapter. It can be both external and internal.

The scanner automatically reads from paper media and enters any printed texts and images into the PC.

The microphone is used to input sound into the computer.

(display) is designed to display information on the screen. Most often, modern PCs use SVGA monitors with a resolution (the number of dots located horizontally and vertically on the monitor screen) of 800*600, 1024*768, 1280*1024, 1600*1200 when transmitting up to 16.8 million colors.

The monitor screen size ranges from 15 to 22 inches diagonally, but most often it is 17 inches (35.5 cm). Point (grain) size - from 0.32 mm to 0.21 mm. The smaller it is, the better.

PCs that are equipped with television monitors (CRT) are no longer so popular. Of these, preference should be given to monitors with low radiation levels (Low Radiation). Liquid crystal displays (LCDs) are safer, and most computers have one.

Designed for printing text and graphic images. Printers are dot matrix, inkjet and laser. In dot matrix printers, the image is formed from dots using the impact method. Inkjet printers have thin tubes in the print head instead of needles - nozzles, through which tiny droplets of ink are thrown onto the paper. Inkjet printers also produce color printing by mixing base colors. The advantage is high print quality, the disadvantage is the danger of ink drying out, the high cost of consumables.

Laser printers use the electrographic method of image formation. The laser is used to create an ultra-thin beam of light that traces the contours of an invisible dotted electronic image on the surface of a pre-charged light-sensitive drum. After developing the electronic image with dye (toner) powder adhering to the discharged areas, printing is performed - transferring the toner from the drum to paper and fixing the image on the paper by heating the toner until it melts. Laser printers provide the highest quality printing with high speed. Color laser printers are widely used.

Speakers output sound. The sound quality depends - again - on the power of the speakers and the material from which the cabinets are made (preferably wood) and its volume. An important role is played by the presence of a bass reflex (hole on the front panel) and the number of reproduced frequency bands (high, mid and low speakers on each speaker).

USB flash drives, in my opinion, have become the most universal means of transferring information. This miniature device is smaller in size and weight than a lighter. It has high mechanical strength and is not afraid of electromagnetic radiation, heat and cold, dust and dirt.

The most sensitive part of the drive is the connector, covered with a cap. The capacity of these devices ranges from 256 MB to 32 GB, which allows you to select a drive of the required capacity, in accordance with your needs. Thanks to the interface, the USB drive can be connected to any modern computer. It works with Windows 98SE/Me/2000/XP/Vista/7, Mac OS 8.6 ~ 10.1, Linux 2.4 operating systems. In Windows you don’t even need to install any drivers: just plug it into a USB port and go.

Needed to input dynamic images into a computer and sound (for communication and the ability to create teleconferences).

Uninterruptible power supply needed in case of a power outage.

Puff, well, in my opinion, that’s all the main thing I wanted to tell you about the computer hardware, the so-called hardware.

The article “Computer Design” was written quite a long time ago. Therefore, if you find an error or find some inaccuracy, please write about it using the comment form. We will be very grateful to you!

Good day, dear readers. Today, any person is at least remotely familiar with a personal computer. This useful device greatly helps in many areas of life. Advanced users will easily distinguish the system unit from the printer, and will also explain the difference. But for people who are encountering such technology for the first time, it is quite difficult. In today's article we will look in detail at how the computer system unit works.

What is it for?

Users who have never delved into the study of computer components believe that the system unit is some kind of box that provides image output to the monitor. And most of them call it a "processor". What does the system unit do?

Its main task is to connect the components located inside with the monitor, keyboard, mouse and other peripheral devices. Well, of course, protection from external influences on internal elements.

Case size

There are two large types of system units: horizontal or vertical. The first ones are placed in a horizontal position under the monitor, but are rare today. The second type of case is more common, often called Tower, which is translated from English as “tower”. Vertical system units can be divided into several more groups: big, midi and mini.

Dimensions depend on user requirements. The most common are Tower mini (small), which take up minimal space but have enough space for subsequent upgrades. Fans of the most modern games need large ones to have room for several video cards. Compact cases are suitable for assembly, which is intended for undemanding tasks.

Another important point of the system unit, on which the subsequent placement of components depends. Currently, two form factors are actively used: AT and ATX. It is important to remember that the motherboard must have the same form factor, otherwise it simply will not fit.

What is included in the system unit

The basic package of the case, as a rule, includes a power supply, which eliminates the need to purchase it separately. Of course, if you want, you can replace it without any problems.
So, the main components:

• motherboard;
• power unit;
• CPU;
• hard drive;

Motherboard

The most basic part of any system unit, without which work is impossible. Its main task is to connect all components and ensure joint functioning. It is the largest and most visible part of the block. The motherboard has connectors for connecting components and peripherals.

The motherboard connectors are located on the rear wall of the system unit. All of them are color coded. This is done to facilitate the correct connection of other devices (keyboard, mouse, monitor, audio speakers). After all, their plugs (most often) have the corresponding color.

power unit

Responsible for distributing energy for each component. It has a set of connectors on the front panel, through which the rest of the system is connected. Usually comes complete with the case, but can be replaced with a more powerful one. In the picture above, the power supply is positioned at the bottom of the case, but most often it is located at the top.

CPU

It is considered the heart or brain of the PC. It is a silicon crystal grown and processed using special technologies. Responsible for processing information; processors from Intel and AMD are especially popular.

It is equipped with a cooling system, which is represented by a fan and a radiator or only the latter. Installed in a designated location on the motherboard. The cost depends on the tasks that will be assigned to the processor, and can reach several thousand dollars.

Video card

Without this component, you will not be able to work with graphics programs, and games will not start. Almost any modern processor has a built-in graphics adapter, which is sufficient for simple tasks. But gamers will have to buy a separate video card. How to connect? Of course, to the motherboard, which has special slots. There are many models on the market aimed at different user tasks.

RAM

Necessary for storing information processed by the processor. True, the RAM works while the PC is turned on, after turning it off everything disappears. The more there is, the better. A lot of memory ensures high speed of processing user data. RAM consists of small sticks that are inserted into special slots. In addition to capacity, an important characteristic is the type of memory.

Hard drive

Unlike RAM, hard drives are needed to store permanent user data. Their main characteristic is their volume, which today is measured in gigabytes and terabytes. The size of the hard drive depends on the user's tasks. Recently, HDDs have been replaced by SSDs (drives without mechanical parts). They work faster, do not make noise and practically do not heat up.

Sound card

It is impossible to imagine a modern computer without the ability to reproduce sound. For this purpose, an audio information output device is designed, which is most often already integrated into the system board and has sufficient characteristics to reproduce audio information. But for professional sound processing on a computer, a separate sound card (internal or external) is required.

Let's finish here. We'll talk about how to connect the components of the system unit together next time. Share the article with your friends. See you again!

In conclusion, I suggest watching a cool video about self-assembling a computer system unit from the channel “Good Choice!”

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If you have not read it, I recommend that you read it before reading this article. Today we will climb into the “holy of holies”: system unit or " systems specialist"in everyday life. To make it clearer, I disassembled my own system unit and took photographs, which I will provide to you as a visual aid, let’s say, system unit device in pictures. Let's start with internal structure of the system unit, and then let's move on to the outside. Let's get started!

To begin with, it is worth mentioning that the system unit can be horizontal in shape (called Desktop), which is usually located under the monitor, or vertical, which is called Tower. The Tower case, depending on the size, can be large, midi and mini. The most common case is the mini tower, which you can see in the photographs. By the way, you can familiarize yourself with the design of the system unit of your personal computer, but you need to be very, very careful and first completely turn off the power to the computer, and only then start doing something. It is advisable to disconnect all the wires, but if you have problems connecting them, it is better not to. We will talk about connecting devices to the system unit in a series of articles, having dealt with. If you need to remove the system unit from under a table, for example, then this must be done very carefully, avoiding shocks and impacts. To see what is in the system unit, I need to remove the side cover by unscrewing 2 screws on the back wall, but the design of the case can be very diverse. The main thing is to carefully examine the case and understand where the cover is attached. It should come off without much effort, so don’t be overzealous. So, the cover has been removed, let's figure out what's needed for what.

Let's start with motherboard, which is also called maternal, and sometimes even affectionately “mother”. And no wonder: she is the largest and (as befits a mother) monitors the horde of other devices and coordinates their work, transmitting a signal from one to another. It’s not difficult to find; the motherboard, as I said, is large. In the photo it is highlighted with a green frame and marked with a number (1) in the corner.

The number (2) hides the processor in the system unit. He is really hiding, because in the photo he is not visible at all. However, it looks like this:

CPU is a specially grown silicon stone, which, moreover, contains an incredible number of other elements: transistors that are connected to each other. The processor is a kind of “brain”, because it processes incoming information. One of its most important characteristics is the clock frequency, which represents the number of the simplest (elementary) operations it can perform per unit of time (second). It is measured in MHz (megahertz - that is, millions of hertz) or GHz (gigahertz - billions of hertz). Quite a lot, isn't it? Usually you can see these numbers in the description of the configuration of the purchased computer or in the advertisement for sale. For example, 3000 MHz. The most common processors are Intel and AMD brands. The processor heats up during operation, so install radiator, which removes all this heat, and is also installed on top cooler- This is a small fan that circulates air and cools the radiator. This is exactly what you see under the number (2), and the radiator is visible underneath it. Let's look again at a larger photo:

The computer operates with information, so it must be stored somewhere. Let's draw an analogy with a person: there are things that we need only during work, for example, a formula. We don’t have to remember it, and it’s impossible to keep everything in our heads, so it’s written down somewhere in a book or notebook. It’s the same with a computer: it stores all the data on drives, and when some data is needed for work and needs to be used, it loads it into RAM(RAM – random access memory). She is numbered (3) in the general photo. It loads because it’s faster to work with it, because this memory is very fast. When the computer is turned off, there is nothing in this memory, everything is erased, just like with us when we sleep - we cannot think at this time. And at this time, the information on the computer is located only on storage devices.

Under the designations (7a) and (7b) and highlighted in yellow, just hard drives. Hard drive is also called hard drive, and in everyday life “screw” or “broom”. Data is stored on it even when the computer is turned off. They are characterized by many parameters, but you only need to keep in mind the volume, which shows how much data can be written there, and the access speed. However, it’s worth getting acquainted with the units of measurement of information in a separate article; let’s leave that out for now. Let's take a closer look at the hard drive from the inside.

We can also see the cables. Naturally, every device needs electricity, so each one comes with a power cable from a power supply, which will be discussed below. And you can also see such a wide cable; in the picture it is labeled “IDE cable”. Don’t be scared, you just need to know that there is an IDE hard drive and SATA, it depends on how they are connected to the motherboard, we won’t go into details, but the latter has a much narrower cable. Information is transmitted through this cable.

Thus, we found out that there is RAM, into which data is loaded as needed when the computer is running from a drive where it is stored permanently. However, when the computer turns on, it needs commands, because its RAM is empty! Imagine waking up and your head is empty! To do this, the computer has a read-only memory (ROM). It contains basic programs that check the status of the system and its readiness for operation and make it possible to interact with the monitor, hard drive, keyboard, and floppy drive. All these programs form basic input/output system (BIOS – Basic Input Output System). When you turn on your computer, you immediately see the operation of this very basic system: these are those white letters and numbers on a black background.

If you paid attention, even if the computer is turned off for a long time, the date and time remains correct. This happens thanks to another microcircuit CMOS, in which this data and data about the computer hardware are stored, the chip willingly transfers this data on demand to the BIOS, after which the computer boots. The motherboard has battery, thanks to which data is not lost in CMOS. It lasts for a couple of years, sometimes you have to change it.

In this picture you can just see 2 sticks of RAM and a free slot for another one. The bar is simply inserted there and clamped on the sides with holders. You can see them in the picture, they are white, and in the general photo they are numbered (3). On the left, under the lower RAM strip, there is just a processor radiator and part of the cooler is visible above it.

Let's look further at what's interesting inside the system unit of a personal computer. In the next photo you can see this battery, thanks to which time runs on the computer even if it is turned off. The photo shows connectors into which you can insert other useful devices.

For example, at the top of this photo you see the network card. In the general photo she is numbered (5). It is needed so that several computers can be connected together so that they can exchange information with each other.

Below you see video card (video adapter), she is numbered (4) in the general photo. It is needed in order to form and display an image on the monitor.

Of course, there may not be such a bar, the video card may be built into the motherboard, but if you need a much higher quality image, if you need to be able to play modern games, then of course the capabilities of the built-in video card are not enough. The video card has its own memory, similar to RAM. And also powerful video cards have their own radiator and cooler, because these hard workers also heat up a lot.

One of these free slots could also be used to install sound card, however, I have it built into the motherboard. Sound engineers and music lovers, and anyone who loves high-quality sound, will certainly purchase such a card.

You should not ignore such an important device as power unit. Number (6) on the general diagram and right in front of you in the next photo.

This massive fellow is responsible for distributing energy between all devices. The power supply, of course, must be stable and the unit powerful. I have 300 watts, but the computer is quite old. Now there is more power, because so are the needs. The system unit even has its own cooler. We will see it in the next article, where we will look at the “exterior” of the system unit.

And finally, we still have several devices that also allow you to save information on storage devices.

CD/DVD drive. Number 9 in the general photo and close-up right above this text. It allows you to write and read information using a laser onto disks. They will be discussed in more detail in the article on information storage. It also comes with a power cable and a cable through which information is transmitted. The main characteristic is the data reading speed.

In some places on the computers there are still oblong slots on the front of the system unit. This is a floppy disk drive (FDD - floppy disk drive). Floppy disks are no longer used anywhere due to their low capacity (that is, they hold little information).

So, a quick inspection of the insides of the computer system unit is completed. We close its lid, tighten the screws, it’s time to connect everything back and get to work!

So, from this article you learned:

How system unit is arranged what is inside it

• what they look like and what they are needed for system unit components