Where on the PC device of the work. The main components of a computer. Personal computer device. Motherboard bus interfaces

In this article I would like to tell you about the design of a desktop computer in terms of hardware. About what's inside: how to distinguish a processor from a video card, and a hard drive from RAM.

The best way to learn is to do it in practice! Be bold, disconnect all the wires from your system unit, unscrew a couple of screws holding the side cover on the back of the case, and slide it, pulling it to the side.

What do you see? Covered in dust, multi-colored boards, wires, fans... No need to close the lid in fear and push your PC back! Now I will explain to you what, why, and why. I will explain to you the structure of your home computer in simple and understandable language!

First, I will list the components that are in your computer anyway; without them, it simply will not work. So, let's begin.

The largest computer board, which plays a key role in the design of the computer. Unlike other boards that face us sideways, the computer motherboard is perpendicular and faces us. This is what motherboards look like:

Other components are connected to the motherboard through special connectors. I’ll please you right away, the connectors are different in size and have special “keys”. Those. You won’t be able to insert a video card into the RAM slot even if you try. So, in principle, you can now assemble a disassembled computer without my help, just plugging it in “where it plugs in.” The main thing when working with iron is not to use excessive force! If the board does not fit, check whether you are inserting it correctly.

Connectors located on the motherboard:

1. Connector processor. For example, modern LGA-1151. Or an old LGA-775. By the way, the number indicates the number of “legs” of the processor.
   Next to it is a connector for connecting a processor cooling fan (labeled as CPU FAN)
2. Connectors for random access memory. Most often you will find DDR2 and DDR3, less often ddr depending on how old the PC is. At the beginning of 2016, DDR4 is also becoming increasingly widespread.
3. PCI-Express x16 to connect a video card. There may be several (for connecting 2 or more video cards in SLI mode)
4. PCI, PCI-e connectors for connecting additional expansion cards.
5. SATA- connectors for connecting hard drives (L-shaped). For old disks - long IDE. Also, a DVD cable is connected to the motherboard via SATA
6. Socket for connecting front computer outputs (LEDs, buttons) power And reset).
7. Pins for connecting USB, AUDIO ports on the front panel.
8. Connectors for connecting case fans(CHA FAN). Often such fans can also be connected to the power supply terminals.
9. Connector for “incoming” processor power.
10. Connector for connecting power to the motherboard.

CPU

The central processing unit, or "stone" in slang, is the "brain" of the computer, processing all data input and output from it. The processor is quite complex. What we need to know about it for now is what it looks like (a square with sides of 4-6 cm and many pins on the “belly”). It will probably have the inscription “INTEL” or “AMD” on it - these are the two main processor manufacturers.

The processor socket (connector) must match the motherboard socket, i.e. The motherboard needs to be matched to the processor. An unsuitable processor simply won’t fit.

Contest ! Whoever is the first to guess what kind of processor is in the photo above and write it in the comments will receive 100 rubles from me for a web wallet! 😉

Almost all modern processors (formerly motherboards) have a built-in video core, and often a fairly good one. This may allow you to stop spending money on buying a separate video card.

Trying to find the processor inside your system unit? I’ll disappoint you, you won’t see it, since it’s hidden under the radiator and cooler (fan), which we’ll get to in the next paragraph of this article about the design of a personal computer.

CPU cooling system

During operation, the processor inevitably heats up. Moreover, it heats up strongly and quickly - if left without cooling, it will reach a temperature of 110 degrees and go “into defense” in less than a minute.

In order to remove heat somewhere from above, a radiator is placed on top of the processor (a large piece of copper or aluminum, a material that conducts heat well). The radiator has a large area of ​​​​contact with the air, therefore, it dissipates heat better. (Remember school physics). For ventilation, a fan is attached to the radiator.

Here's what it looks like:

Since it is impossible to make the contact surfaces of the processor and the radiator perfectly smooth, to eliminate the air gap between them, apply thermal paste.

The more powerful the processor, and the greater the load on it, the more it will heat up, and the more massive, powerful and expensive a cooling system needs to be installed on it.

RAM

“Fast” PC memory into which the operating system and other programs (Word, browser, video player, etc.) are loaded. RAM is, so to speak, a “gateway” between a relatively slow hard drive and the processor itself.

The larger this “gateway”, the more information (to which you need quick access) you can load into it. In other words, the more RAM you have- the more programs you can run at the same time. Together with a couple of browsers (with a bunch of open tabs), you can open Word, Photoshop and a bunch of other programs, and your computer won’t slow down.

More modern memory sticks have a correspondingly higher data exchange rate with the motherboard.

Based on the year you bought your PC, you can already estimate what kind of RAM it costs: DDR (2001), DDR-2 (2004), DDR-3 (2010), DDR-4 (2015).

This is what RAM looks like. You can’t confuse it with anything :) Pay attention to the “keys” and the number of contacts that distinguish one memory from another.

Installed and secured using special latches, they themselves should, when you press the bar on top, snap into place when the memory “enters”. I repeat - it doesn’t fit, check again if it’s there key.

The motherboard in the picture above is a “transition” one. Those. You can “insert” both DDR2 and DDR3 into it.

By the way, you can check your RAM for errors right now! How to do this - read the article.

HDD

The hard drive is the place where all the information on your computer is stored: the operating system, all programs, all the contents of the desktop :), photos, music, videos, in general All. One of its main characteristics is volume. The larger it is, the more data you can write to your hard drive. For 2016, the most popular ones are hard drives from 500 Gb to 2000 Gb, although there are both more and less.

Hard drives fail quite often. Here's what I've accumulated over a couple of months. Most likely a coincidence, but 4 out of 5 - Seagate :):

Until recently, a hard drive with a motor was the “bottleneck” place in a PC in terms of speed. Until solid-state devices became widespread in 2012 SSD hard drives that have less capacity for the same price, but several times greater speed.

On my PC I use a 120Gb SSD drive “for the system”, and a slower 2 TB SATA drive for storing all other data. As I advise you, the computer in this configuration simply “flies”!

power unit

The power supply distributes electricity to all components of the computer. For more powerful video cards and processors, a more powerful unit is needed.

The many wires coming out of the power supply are power connectors all PC devices:

1. Molex - for old HDDs and CD-roms, as well as for coolers
2. SATA - for hard drives and DVD drives
3. 20/24-pin for motherboard
4. 4/8-pin for processor power
5. 6/8-pin for additional video card power supply.

I will tell you more about the design of the power supply, as well as about repairing power supplies in the following articles on the site.

Frame

The computer case is directly what all the other components fit into. The cases differ in size, steel thickness, types of mounting hard drives and other spare parts.

I do not recommend keeping the case open all the time - more dust will fly in, and it will need to be cleaned more often, and the necessary air circulation will be disrupted.

Components that may not be present in your system unit.

I listed above required computer components, which are in every PC anyway. The components described below may not be included in your PC. Nowadays, many motherboards have a built-in video card (more often, the video card is “built-in” to the motherboard). Also, the computer can work quite well without a CD drive and other “extras”.

So let's continue to study device personal computer.

On almost all new computers, the video card is most often built into the motherboard or processor. But in terms of power, the built-in video core naturally pales in comparison to modern gaming video cards.

The video card is inserted into a special PCI-E x16 slot, of which there can be two on the motherboard (for using two video cards simultaneously in SLI mode). In computers from 10 years ago you can find an AGP video card. It often has a massive cooling system that also takes up the adjacent slot on the motherboard.

May have a 6/8-pin connector for additional power, which must be connected from the power supply.

CD/DVD drive

Well, everything is clear here. Even grandma knows the drive is for reading discs. Most PCs have CD/DVD write drives. In more modern ones - BLUE-ray. Personally, I use it very rarely, so I can write down a blank or two.

Card reader

A device for reading memory cards of all formats - SD, microSD, Memory Stick PRO Duo, CompactFlash and others. Useful for those who often download and upload materials from their phone and camera.

Expansion cards

This includes boards that expand the hardware capabilities of your computer, adding new inputs/outputs to it to connect various devices.

Here are a few of the most common:

• TV tuner. To watch cable TV on your computer. You can also use it to digitize videotapes; you can read about this in one of the following blog articles on the site. Subscribe!
• Sound card. Nowadays, a sound card is built into almost all motherboards, but if you want to achieve better sound quality or want to connect a modern speaker system, you need a more powerful and expensive sound card.
• USB controller. You can add additional USB inputs, including the now popular USB 3.0.
• Outdated COM, LPT, RS-232 controllers. It may be useful to someone.
• SATA controller. If you have run out of SATA outputs on your motherboard, or you want to connect an external hard drive via the high-speed e-SATA interface.

Additional fans, their rotation speed controller.

For better ventilation and air exchange, additional fans can be installed on the walls of the case - on the back, on the side. above, in front. They are connected to the power supply via a molex connector, or to the motherboard via a 3-pin.

Also, in advanced cases, a fan speed controller can be installed.

Modding is a special device for a home PC.

In general, modding is a separate topic. The simplest thing you can do with your system unit is to install a backlight. And then - a flight of unlimited imagination. 🙂

Computer design is simple!

So, you have found out what they are, what they look like, and why all the main components in the system unit are needed.

Agree, now the computer structure doesn’t seem so “incomprehensible to mere mortals”? 🙂

If you come across a “crap” in your PC that doesn’t fit any of the points in this manual, write in the comments, let’s try to identify the “beast” together.

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System unit

The main part of a personal computer is the system unit. Yes, this is the same box that stands on someone’s desk, on the floor under someone’s feet and makes noise, I don’t mean a laptop, everything is compact and quiet there. That's where all the main components of the computer are inside. In this very box, the most important elements of this amazing invention of mankind are hidden, where we will now look.

We stroke its rough sides, and quietly cherish and cherish our selfish interests that this piece of iron will finally provide me with material well-being, and I will go on vacation to my godfather in Likino-Dulyovo and finally buy myself a bicycle.

So:

Here in such a beautiful (sometimes not very) body and all the main components of our friend are located.

Motherboard - this is all that even if we spend another life learning how it was all made and embodied in such cute plates and cylinders connected to each other by beautiful threads, we will not know how it all works. We don't need it. Let us admire this great creation of man and forget about it. Because we have other tasks.

Processor - the heart of the computer. In his artificial brain, all those calculations take place, which are then converted into streams of the necessary information, which we will eventually turn into the banknotes that we need so much.

RAM(RAM). — a system for storing short-term digital information for processing data arrays, inserted into the motherboard, into the appropriate connectors, and has a high processing speed. In short, a very necessary system and he, the computer, uses it to the fullest and as he pleases.

Sound card, it is also called audio card - serves to reproduce sound; it exists as additional equipment that allows you to output sound to acoustic devices. It is inserted into special connectors (slots) on the motherboard. Typically, computers come built into the motherboard.

Video card(Also graphics card, video adapter) - the device is used to convert a digital signal generated in the processor into a signal for output to devices intended for viewing images (monitors, televisions). Also in modern computers it is supplied integrated into the motherboard. But if you need high-quality output to the monitor, with high speed. then you should purchase more serious and expensive video cards, with a large amount of memory, sometimes costing more than the computer itself. But this is not our story.

HDD(HDD, hard, hard drive) - a storage device, a drive on hard, usually aluminum, less often glass, rotating plates coated with a ferromagnetic layer of chromium dioxide. The operating principle of the disk is based on magnetic recording. The hard drive is the main storage device in modern computers.

DVD drive- another name Optical drive, which uses a laser to read recorded information, as well as write (burn) onto an optical storage medium, which is a special plastic disk (CD, DVD)

And finally, all these systems are powered by electrical energy Power unit. It rectifies, reduces the network electricity to the required amount in Volts and supplies it to computer systems for their stable operation. Everything is as simple as the world.

Of course, when the computer is running, the chips heat up, and compact fans are used to cool them. They do their job well, but over time they wear out and begin to make noise. This is not a big problem, they are sold in every component store and cost a penny. You can always change them and not worry about their serviceability.

Periphery

Peripherals are devices that are connected to the system unit via cables into the corresponding slots (connectors) defined for them. And although they are usually called accessory devices, they are still integral parts of the computer.

Keyboard- a system for entering information (with fingers) into the computer from its user. People call her affectionately “Klava”. One of the main devices. There are different keyboards, I personally love the white Klava.

Mouse is a mechanical manipulator, brilliantly invented by an unknown inventor, which converts hand movement into a control signal. Without it, it’s difficult to imagine working with a computer. There are alternatives to the mouse, these are the so-called scrolls, a ball rotated by the palm, I tried it, it’s inconvenient. But everything has a place in PC operation, and “To each his own,” as it was written on the gates of the Auschwitz concentration camp.

And finally, the most pleasant periphery of our personal computer, which we look at most, in which we see the magical world of the wonderful transformation of human thought into reality, which makes us think and dream, work and enjoy, which arouses curiosity about our vast world of knowledge, which makes us to work and think - this is ours Monitor. And I don’t even want to describe the processes of obtaining an image on this flat plate. Let it remain a mystery for us, let the intrigue remain, and we, like children, remain as naive and dreamy.

Computer structure with pictures

One of the first questions that novice users have is: “How does a computer work?” After all, in order to work confidently on it, you need to understand its organization and understand what is included in its composition. It is this information that will be discussed in this article.

General form

Any modern one includes the following elements:

• Monitor.
• System unit.
• Input and output devices.

The monitor is designed to display information. With its help, user interaction with the computer is easily and simply organized. The system unit connects individual components located outside. The monitor and all peripherals are connected to it. But how the computer works inside the system unit will be described in the next section. There are many components involved and need to be addressed separately. Now let's find out how a computer works from the point of view of organizing input and output. This class of devices includes the entire mouse, keyboard, scanner, and printer. The first three are used only for entering information. The latter displays it on paper. Nowadays, devices that combine not only a printer with a scanner, but also a copy machine have become increasingly popular.

System unit

The system unit contains the following components of a personal computer:

• Processor with fan for cooling.
• Video card.
• Motherboard.
• RAM.
• HDD.
• Power unit.
• Card reader.
• CD drive.

The processor is the main chip in the system. It is installed on the motherboard. It consists of a control unit, a cache (fast memory for storing the most important data), memory registers and an arithmetic-logical unit. This is how the computer processor works. It gets very hot during operation. Therefore, fans called coolers are used to cool it.

The video card is installed into the main board of the PC. Its main task is to display images on the monitor screen. It is equipped for these purposes with a separate powerful chip and its own memory. The motherboard is the unifying element of the entire system. Everything is installed or connected on it.

The power supply is responsible for organizing the power supply to the system. This is a separate “box” that is installed on top or bottom of the back side. The card reader and CD drive are similar to each other. They work with removable storage media. The first organizes work with various types of flash drives, and the second with CDs and Blu-ray, depending on the model).

Conclusion

It is important to understand how a computer works. This will make it easier to work on it. Also, if malfunctions occur, it will be possible to diagnose and eliminate them. It is from this position that you need to know and understand the structure of a modern computer.

Hello dear visitors of the blog site. Today we’ll talk about computer devices, or as they usually say, “hardware” that can be found in the computer system unit. This way you will understand what a computer is made of. The hardware of a computer, or as it is fashionable to say “hardware,” remains a mystery even to many experienced users. In this article I’ll tell you about hardware devices, thereby filling the gap, of course, if you have one, and if you are familiar with them, then we’ll refresh your memory a little.

First of all, let’s divide what is commonly called a “computer” into two groups:

• System unit. This is that big (or not very big) box to which everything is connected.
• Peripherals. You can read about peripheral devices in my article « » These are all other devices that help you work with a computer. Their main feature is that they are located outside the system unit and connected to it from the outside.

System unit device

The system unit is the main device of the computer. Only by looking inside the computer can we figure out what the computer is made of.

1. Power unit.
2. RAM.
3. Hard disk drive.
4. Floppy disk reader.
5. Optical disc reader.
6. Additional devices.

Points 1 to 5 are mandatory; you will find them in any system unit. The rest may not exist or they may be in the form of peripheral devices, that is, connected externally.

What does computer consist of:

Now let's tell you in more detail about each component.

power unit

This computer device is an important component in the computer! The abbreviated name is BP. The main characteristic is the maximum output power. It is measured in Watts (W), in English Watt (W). For a home computer, the power supply is usually 350-450 W, for a powerful gaming computer it is 600 W or more.

The importance of this component is often underestimated. When buying a computer, you may be offered to save money by installing a lower-quality power supply. This is highly not recommended, since the power supply is the source of energy for all other components of the system. If a low-quality power supply breaks down or has some problem in the electrical network, it can damage other components of the system. In addition, cheap and low-quality models often indicate power values ​​that are far from reality. That is why the computer power supply must be from a trusted manufacturer and have sufficient power.

Name options: motherboard, mother, main board, MotherBoard, MainBoard. It is to the motherboard that all devices located inside the system unit are connected. It is the main board in the system. Let's take a closer look at its contents:

• Socket – connector for connecting a processor. Depending on which socket your motherboard contains, you may only be able to use a certain group of processors.
• Slots for connecting a RAM module. In personal computers their number varies from 2 to 4. By type they are: DDR, DDR2 and DDR3. Modern motherboards may have two types of slots at once.
• Connectors for connecting devices and storing data. For ordinary PCs, they come in two types: a wide elongated connector with 39 pins in two rows and a small almost rectangular connector with an “r”-shaped middle. The first is a parallel interface called IDE (Integrated Drive Electronics) and its second name is PATA (Parallel ATAttachment). The second is the SATA (Serial ATAttachment) serial interface.
• Expansion slots. These are connectors that are used to connect additional devices. They are an elongated connector located horizontally on the lower left side of the motherboard. This is where the video card, network card and other devices are inserted. These connectors usually connect devices to the motherboard via the PCI interface (Peripheral component tinterconnect) or its derivatives PCI Express, etc.
• Chipset. This is a set of chips that provide communication between system components. Usually it can be divided into the so-called north and south bridge. The north bridge is a memory controller, that is, a part that ensures data exchange between the central processor and RAM. On modern platforms, the memory controller can be integrated directly into the central processor. The south bridge is an I/O controller, a part that provides communication between the processor and interfaces such as SATA, IDE, PCI, USB and others.

The required components of the motherboard are listed above; they are also united by the fact that they are visible only from inside the system unit.

If you look at the back of the system unit, you can see many connectors that are also physically located on the motherboard. They are located on the left side, approximately in the middle and are enclosed in a metal “frame”. Please note that your computer may not have many of them, it depends on the specific motherboard model.

• Connector for mouse and keyboard. These are two round connectors, one purple (for the keyboard) and the second green (for the mouse). This interface is called PS/2 (colloquially PS in half).
• LPT port. This parallel interface was invented as a printer port and was actively used for other purposes. Today, in motherboards, it is increasingly rare to find it on board.
• COM port. Another obsolete serial interface. This port is actively used as an interface for configuring equipment.
• USB (Universal Serial Bus - universal parallel bus). This is the most popular way to connect peripheral devices to a modern PC. Used to connect a variety of devices: mouse, keyboard, scanner, printer, portable hard drives, flash drives, etc.
• Video connector VGA, DVI. These are interfaces for connecting a monitor. If your motherboard has such a connector, then it has a built-in video adapter. It will be quite enough for work, but if you intend to play games on the computer, you will need a discrete (separate) video card, which will be inserted into a special expansion slot.
• RJ-45 network connector. The interface is used to connect a computer to a local area network of the Ethernet standard.
• Group of audio connectors Jack 3.5. Used to connect a speaker system and a microphone. Green connector for connecting speakers and pink for microphone.

Now I propose to clarify one important point. If any connector is located in a vertical “frame” in the middle of the system unit, then the device to which it belongs is built into your motherboard. If you have a discrete video card, modem or anything else, then it is connected to the motherboard through an expansion slot and the connector of the device itself will be located below horizontally.

Central processing unit (CPU), in English CPU (Central processing unit). This is a chip that executes software commands, performs calculations, performs logical comparison operations, and roughly speaking, “thinks.” Therefore, the processor is often called the “brain” of the computer.

The main characteristics of the device are: bit capacity, clock frequency, power consumption, number of cores, architecture.

Bit capacity indicates the amount of information transmitted per unit of time over the data bus. Available in 8, 16, 32 and 64 bits. Accordingly, the higher the bit depth, the faster the processor runs. Clock frequency shows how many clock cycles (elementary operations) the CPU performs per unit of time. Power consumption indicates how much heat the processor generates when running.

Some time ago, the two main processor manufacturers - Intel and AMD - in their competition, tried to increase the clock speed of their processors as much as possible. But we were faced with the fact that after overcoming a certain threshold, energy consumption and heat transfer begin to increase nonlinearly. The solution was multi-core processors. This means that one CPU contains several crystals that distribute the computing load among themselves. The most widely used devices now are 2-core devices, although this is not the limit; there are processors with 4 or more cores.

The architecture shows how work is organized inside the processor. Although this parameter does not add the desired gigahertz, it can have a very significant impact on performance. Intelligent organization of work, as we know, costs a lot.

RAM

RAM is a random access memory (RAM), in English – RAM (Random Access Memory). This memory area is volatile, that is, without “power” the data is not saved in it. The RAM stores information that must be processed by the processor in real time. During operation, RAM contains data from the operating system and running user programs.

Today, RAM modules of the SDRAM DDR3 standard are relevant; before them there were SDRAM DDR 2 and SDRAM DDR 1 (of course, they can still be found). Each new generation had a number of serious advantages over its predecessors: throughput increased, energy consumption decreased.

HDD

A hard disk drive, or HDD (Hard Disk Drive) in English, is a read-only memory device (ROM). This computer device is also called a hard drive or hard drive.

This type of memory is not non-volatile, that is, data is retained in memory after the power is turned off. It is this computer device that contains all the user data: movies, music, documents and everything else.

The hard drive consists of several round plates that rotate on a spindle. These plates are coated with a ferromagnetic material, divided into many cells, each of which stores one bit of binary information. A special head reads and writes information, which moves to the desired location above the surface of the disk.

They differ in the amount of stored information, connection method, form factor, and spindle speed.

As mentioned earlier, there are two types of connection method: IDE and SATA. The first one is almost never used anymore, since serial SATA is faster and more convenient. According to the form factor, HDDs come in 5.25 (discontinued production); 3.5, 2.5 inch, 1.8 inch, 1.3 inch, 1 inch and 0.85 inch are the sizes of the plates that contain the information. Desktop PCs usually use 3.5 HDDs, laptops 2.5. The faster the rotation speed, the higher the speed of writing and reading data. In 3.5 models, the speed is usually 7200 rpm, in 2.5 - 5400 rpm, although there are also faster models of hard drives for laptops.

Floppy disk drive

A floppy disk drive, in English FDD (Floppy Disk Driver), is also called Floppy or simply floppy. This is a floppy disk reader. Roughly speaking, a floppy disk is a miniature hard drive, only instead of metal plates there is a flexible film base, and the head and drive motor are located in the disk drive. The size of floppy disks is 3.5 inches (5.25 inch floppy disks have been used for a long time). The floppy disk capacity is 1.44 MB. Floppy disks, in addition to their small volume, have a serious drawback - they are very unreliable, the information on them may become unreadable due to exposure to magnetic fields or shock. Because of this, this type of media is almost never used today.

Optical drive

Optical media are plastic discs coated with a special layer. The disk is illuminated by a laser, and information is read from the reflected light. Optical discs come in several types: CD (Compact Disk), DVD (Digital Versatile Disc - digital multi-purpose disc), Blu-ray Disc (from English Blue Ray - blue ray). CD and DVD discs come in three types: ROM (Read Only Memory – read only), R (Recordable – writable), RW (Re-Writable – rewritable).

Drives (disk drives) for reading optical discs are called the same as media. Moreover, the drive is called by the abbreviation of the last generation in line that it is capable of reading. That is, a DVD-ROM drive reads DVDs and CDs, but a CD drive only reads CDs. Also, drives are divided into those that can only read (CD/DVD ROM) and drives that can read and write discs (CD/DVD RAM).

CD capacity 700 MB. DVD discs can be single-layer, double-layer and double-sided, the volume of regular is 4.7 GB, double-layer 8.5 GB, double-sided 9.4 GB, double-sided double-layer 17.08 GB (the latter is rare). Blu-ray Disc can store 25 GB, double layer 50 GB.

So, we have just looked at the main components that make up a computer. But we must not forget about devices that are not always included in the computer.

Additional devices (peripherals)

Additional devices can be devices that are inserted into the motherboard. A discrete one (on a separate board) can be a video adapter, sound adapter, network adapter, wi-fi, modem, USB controller and many other devices.

I hope this article has fully explained to you what a computer consists of. And after reading it, the world of hadware (that’s what computer hardware is called) will become a little closer and clearer to my readers.

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 the side panel and look inside, then only in appearance 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 disk drive (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 (more often called motherboard), which, in turn, contains:

• microprocessor;
• mathematical 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). We will look at its elements in bold below.

And now, in order, about the system unit:

1 . Everything is clear with the power supply: it powers the computer. Let me 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 model of a 16 KB hard drive (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 the motherboard, ATA and IDE are distinguished.

3. A 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). Magnetic disks use magnetic materials with special properties as a storage medium that allows them to record two magnetic states, each of which is assigned binary digits: 0 and 1.

4 . Optical disk drives (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. First, reading DVDs uses a laser with a shorter wavelength than reading CDs, which has significantly increased 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. A serial port transmits information bit by bit (slower) over a small number of wires. A mouse and modem are connected to the serial port. Through a parallel port, information is transmitted simultaneously over a large number of wires corresponding to the number of bits. 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 a mouse to a 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 machine blocks and to perform arithmetic and logical operations on 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). The clock speed indicates how many elementary operations (cycles) the processor performs in one second.
Intel Pentium processors and its economical version Celeron are respected in the market, and their competitors - AMD Athlon with the economical version Duron are also appreciated. Intel processors are characterized by high reliability, low heat generation and compatibility with all software and hardware. And AMD shows greater speed with graphics and games, but is less reliable.

Computer memory can be internal or external. External memory devices include the already discussed HDD, FDD, CD-ROM, DVD-ROM. Internal memory includes permanent storage (ROM, ROM), random access memory (RAM), Cache.

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

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 can always be replaced, whereas if the built-in video card fails, you will have to replace the entire motherboard. For 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). Dot (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 and 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).

Uninterruptable power source 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!