Types of PC cases. System unit. A14. External memory includes
Tests for grade 7 on the topic “Computer structure”
1. A device for entering information from a sheet of paper is called:
plotter
streamer
driver
scanner
Answer: 4
2.Which PC device is intended for displaying information?
CPU
monitor
keyboard
record player
Answer: 2
3.Driver is
long-term storage device
a program that controls a specific external device
input device
output device
Answer: 2
4.Operating systems are included:
database management systems
programming systems
application software
system software
Answer: 4
5.Which of the following refers to devices that output information from a computer? Please indicate letters in your answer.
scanner
Printer
plotter
monitor
microphone
speakers
Answer: 2, 3, 4, 6
6.What number system does the computer use?
in binary
in hexadecimal
in decimal
all answers are correct
Answer: 1
7. Personal computer cases are:
internal and external
Answer: 1
8.Scanners are:
horizontal and vertical
internal and external
manual, roller and tablet
matrix, inkjet and laser
Answer: 3
9.Printers cannot be:
tablet
matrix
laser
jet
Answer: 1
10.You can save information before turning off your computer
in the magnetic disk controller
in ROM
Answer: 2
11.Operating system:
software system that provides working together all computer devices for information processing
a system of mathematical operations for solving individual problems
planned repair system and Maintenance computer equipment
document scanning program
Answer: 1
12. A device that converts analog signals into digital signals and vice versa is called:
LAN card
modem
CPU
adapter
Answer: 2
13.Which of the following applies to computer input devices? Please indicate letters in your answer.
scanner
Printer
plotter
monitor
microphone
Answer: 2, 4
14.In what PC device is information processed?
external memory
display
CPU
mouse
Answer: 3
15.Input device - joystick - used:
for computer games
when carrying out engineering calculations
for transmission graphic information to the computer
for transmission symbolic information to the computer
Answer: 1
16. There are no monitors:
monochrome
liquid crystal
CRT based
infrared
Answer: 4
17.External memory includes:
modem, disk, cassette
cassette, optical disc, tape recorder
disc, cassette, optical disc
mouse, light pen, hard drive
Answer: 3
18.Operating systems:
DOS, Windows, Unix
Word, Excel, Power Point
dr. Web, Kaspersky Anti-Virus
Answer: 1
19.When working with text editor The following hardware is required personal computer:
keyboard, display, processor, random access memory
external storage device, printer
mouse, scanner, hard drive
modem, plotter
Answer: 1
20.Which of the following applies to storage media? Please indicate letters in your answer.
scanner
flash card
plotter
HDD
microphone
Answer: 2, 4
21.Minimum composition of a personal computer...
hard drive, disk drive, monitor, keyboard
monitor, keyboard, system unit
printer, keyboard, monitor, memory
system unit, modem, hard drive
Answer: 2
22. Which of the following input devices belongs to the class of manipulators:
touchpad
joystick
microphone
keyboard
Answer: 2
23.Printers are:
desktop, portable
matrix, laser, inkjet
monochrome, color, black and white
CRT based
Answer: 2
24.Which of the following applies to internal memory? Please indicate letters in your answer.
HDD
RAM
ROM
diskette
magnetic disk
Answer: 2, 3
25. In what PC device is information processed?
external memory
display
CPU
Answer: 3
26. Device for displaying text and graphic information on various solid media
monitor
Printer
scanner
modem
Answer: 2
27. A type of printer in which an image is created by mechanical pressure on the paper through a ribbon containing ink. Either symbol templates or needles are used, structurally combined into matrices.
impact type (matrix)
inkjet
photoelectronic
Answer: 1
28. The central device of the computer that processes information is:
1. monitor
2. processor
3. printer
4. speakers
Answer: 2
29. On a standard keyboard:
1. 104 keys and 3 indicator lights
2. 106 keys and 2 indicator lights
3. 104 keys and 4 indicator lights
4. 106 keys and 1 indicator light
Answer: 1
30. Personal computers are:
1. desktop and pocket
2. Pocket and portable
3. desktop
4. desktop, portable and pocket
Answer: 4
31. What type of computer is the most productive and is intended for permanent installation at home or in the office?
1. pocket
2. portable
3. desktop
Answer: 3
The case of the system unit is a kind of quintessence of its owner’s ideas about his personal computer and can serve as the owner’s business card. Yes, at first glance you can get some initial idea about the habits, character traits and education of its owner, as well as about the purposes for which this personal workplace. Naturally, all of the above is true only if the housing was chosen by the user independently and was not imposed on him.
What types of cases are there?
In terms of their design, the housings are a parallelepiped, in which one pair of planes is clearly larger in area than the others. Currently, two chassis architectures are common in the desktop and workstation chassis market. A case that uses the largest plane as a base is called a desktop case. Accordingly, the housing in which the specified surface is located vertically is called a tower. Each type is divided into a number of subtypes, differing in linear dimensions and expansion capabilities.
Desktop (desktop version of the case). Desktops are the oldest type of case, and their history dates back to the first personal computers. The minimum height of the case is determined by the horizontal position motherboard. As a rule, desktops were used as a monitor stand, thereby saving space on the desktop. Expansion options of this type The cases are very small: two (less often three) 5.25-inch and one or two 3.5-inch bays with external access. In addition, there are two internal compartments for installing hard drives. Currently, the desktop is becoming less and less common on user desktops, but large companies (IBM, Compaq, Hewlett-Packard, etc.) still produce office series desktop computers with this architecture. This is quite justified, since for an office computer it is much more important to minimize the space occupied on the desktop.
The idea of creating a miniature office computer marked the beginning of further minimization of desktop cases, which led to the emergence of slim-type cases (thin, low-profile desktops), which provide only one low-profile external 5.25-inch bay, one 3.5-inch wide bay and internal basket for installing a hard drive. Naturally, a regular motherboard can no longer be used in such a case, and therefore boards with a reduced area (micro-ATX) are specially produced for them. In addition, early models of slim cases (non-ATX and early ATX) were supposed to use herringbone motherboards, in which the expansion slots were located parallel to the motherboard due to their placement on a separate additional board. In addition, to reduce the height, some slim cases require the use of expansion cards with a reduced profile, which does not allow the use of conventional expansion cards in these cases. Part of this problem of component placement in low-profile desktop cases is alleviated by the use of all-in-one motherboards with integrated audio, video and network adapters. When minimizing space, expansion slots and RAM connectors are sacrificed first of all. For home computer this is not very healthy, but for office use such a sacrifice is quite advisable, since office computer it is bought ready-made and is not expanded during the entire period of operation (two to three years) (increasing RAM does not count).
The disadvantages of desktops emerged during the further evolution of personal computers. The displacement of 14- and 15-inch monitors and their replacement with 17- and 19-inch ones made it impossible to use the case as a stand - due not only to the significantly increased weight of the monitors, but also to changes in the geometry of the workspace: the monitors began to rise greatly above the tables, violating the ergonomically justified vision angle. In addition, the desktop configuration case takes up a lot of valuable desktop space, and the low location of the ventilation holes above the base (read - above the table surface) leads to rapid dusting of the internal space of the case. Further development of peripheral devices, a direct consequence of which was the inclusion of a CD drive as a mandatory minimum necessary equipment, increased the requirements for the number of compartments with external access. To meet all the new requirements for a personal computer case, a case layout with a vertical arrangement of the motherboard, called Tower, was developed.
Tower (tower version of the body). In terms of its architecture, the tower is a desktop version of the case rotated 90°, where the number of compartments with external access has been increased. In accordance with the number of external compartments, all tower versions are divided into the following subclasses: micro-tower (1 external compartment 5.25"), mini-tower (2 external compartments 5.25"), midi-tower (3-4 external compartments 5 .25" and finally, tower (big tower, full tower), which provides from 5 to more than 12 external 5.25" bays.
Let us make a reservation that such a division seems rather arbitrary. Each type of enclosure has its stalwarts and is tailored to specific needs. For the significant expansion possibilities of tower buildings, you have to pay for the larger area needed to organize a workplace. This is caused by the need to place the monitor on the table, and not on the system unit, as was the case with desktops. But there is a silver lining: the tower-type body, facing the user with one of the large faces, is able to separate your workspace from the room and personalize your “living space”. Not to mention that the largest edge of the case is an ideal place for sticking stickers with a list of “forget-me-nots” and phone numbers. From our point of view, midi-tower and full-tower formats are closest to the optimal (universal) format. True, the concept of “optimality” greatly depends on the needs of the user and the amount of time he spends at the computer. Therefore, we will sequentially consider all types of towers and indicate their pros and cons.
Micro-tower is today positioned on the market as the optimal solution for the office. The miniature size combined with the small footprint required for installation on a desk invariably attracts the attention of corporate users. We emphasize that this is the opinion of the manufacturers. From a user point of view, this case is inferior to a thin desktop version due to the need to allocate additional space for the monitor. As a result, the computer will occupy at least twice as much area on the table. The positive aspects here are the high location of the power supply fan above the table surface (the amount of dust collected by the power supply is reduced) and the ability to use standard expansion cards (compared to the thin version).
Mini-tower compares favorably with micro-tower by a large number of compartments with external access (2 5.25" bays and 2 3.5" bays or more) powerful block power supply (we will talk about power sources in detail below). This type of case does not have any special advantages over a microtower, except for the ability to use full-size ATX-compatible motherboards. The presence of additional external compartments does not save this type of case from the dubious title of “non-upgradeable”.
Midi-tower cases are currently the most widely represented on the market due to their versatility. They differ from the mini version by the presence of 3-4 5.25” compartments, which provides ample room for expansion. In addition, midi-tower cases provide mounting slots for (sometimes more) additional cooling fans.
Finally, tower-type cases (tower, big tower, full tower) can be used for computers that perform the functions of servers and workstations. Huge number of externally accessible compartments provide excellent expansion and installation options additional devices. It is reliably known about the existence of a tower with 9 5.25” compartments; there are even eyewitness accounts of “monsters” with 15 such compartments. Cases of this type are characterized by the absence of 3.5” bays, since devices of this form factor can be installed in a larger bay using a special frame or slide. For full tower cooling, it is possible to use up to 6 fans mounted on the case, not counting those installed additionally.
Case power supplies
The power supply is the bottleneck of any computer. This is primarily due to the fact that it is very difficult to accurately diagnose problems with it during normal operation (except in the case of its complete failure). As a rule, we learn about his problems indirectly, for example, by unexpected computer freezes, blue Windows screens or random reboots. It is rarely possible to reliably link these phenomena to the power supply. As a rule, we first change the motherboard, then the RAM, and only then do we remember the power supply.
The service life of the power supply can reach five to seven years. Its service life can be extended by minimizing the number of on/off cycles, as well as regular (every year and a half) cleaning of dust accumulated inside. In addition, it is not recommended to use it at the limit - the power supply should always have a power reserve. All voltage ratings used in the computer are formed in the power supply. The accuracy of their formation and stability are a guarantee of the reliability and uninterrupted operation of the entire system as a whole. As a rule, the power supply has 1 connector for connecting to an external network and a power button. This is due to the fact that the ATX standard assumes a constant supply of supply voltage to the motherboard. The AT standard (the predecessor of ATX) used a single toggle switch to turn on the computer. In addition, the monitor was often powered from the computer’s power supply. As a result, the power switches often failed (simply burned out), since modern monitors consume a lot of current when turned on.
Each type of case has its own power supply values: ATX desktop and micro-tower cases, as a rule, use weak power supplies (up to 200 W). They are quite sufficient to power a minimum set of devices, which are often limited to the configuration of office workstations. For older models of the tower family, power supplies are available in 200, 235, 250, 300 and 350 W. The latest figures may seem “reinsurance”, but modern processors (especially AMD), graphics accelerators and hard drives are placing increasingly higher demands on the power of the power supply. For the vast majority of computers, a 235 W power supply will be sufficient.
A number of power supplies have a built-in surge protector (not to be confused with a UPS). This seems especially important if we remember that the motherboard in ATX computers is constantly under voltage and a surge in the input voltage can easily damage it. It would also be a good idea to check if the power supply has certificates from one of the well-known certification authorities (for example, FCC, TUV, UL). A good power supply costs no less than $35, so a case that costs $40 should automatically raise red flags.
Case design
At its core, a desktop or workstation case is a chassis for housing a number of expensive and fragile equipment. A kind of computer communal apartment. The challenge for manufacturers is to squeeze the most large quantity equipment, without compromising access inside and ease of use. They, in their opinion, successfully achieve this even in slim and micro-tower cases. You believe? I am not, and I will try to explain it. Let's look at the problem of component compatibility using the example of a tower family case. Obviously, the computer components must be located at some distance from each other, and not only for better heat transfer, but also to ensure the exclusion of mutual physical damage. In this case, the protective distances must be calculated taking into account the most “inconvenient” configurations, which to some extent ensures the universality of use of the housing. Unfortunately, case manufacturers do not always correctly perform this operation, which is simple in principle. It is not uncommon for the 5.25” bay border to be only 1 cm above the surface of the motherboard. Moreover, it is precisely in the place where the vast majority of manufacturers place connectors for connecting hard drives and RAM. What the producers were thinking remains a mystery. The example given is by no means out of the ordinary. I have seen how the front panel of a CD-ROM drive was forced to extend 2.5 cm beyond the front panel of the case, since it was not possible to push it in completely - the standard drive rested against the end of a standard motherboard. That is why the use of microtopology packages requires careful checking for linear compatibility with the equipment used. Note that midi-tower and tower cases fundamentally do not have this problem.
In addition to the linear separation of components, ease of access inside is also important. As a rule, to do this, remove the left side edge of the case (for a tower) or the upper part of the casing (for a desktop). In addition, for tower-type cases it is possible to remove the entire casing (screwless fastening with latches is more often used) and remove the left and right walls separately. It is impossible not to mention the ideal option for access to the inside of the case, keeping in mind the PowerMac G4. In this model, the side wall lowers on a hinge like a ship's ramp, along with which the motherboard attached to it rotates, opening up very convenient access to both the board itself and the compartments with external access.
Finally, an important quality characteristic of the case is the presence of convenient controls and displays on the front panel of the case. As a rule, there are buttons for turning on (Power), reboot (Reset) and, less often, a button for turning on the energy-saving mode (Sleep). The requirements for their implementation are quite simple: the Power button should be clearly visible and slightly recessed into the body to avoid accidental pressing; The Reset key is most preferable in a miniature design with slightly difficult access in order to avoid the same accidental presses. With the indication, the situation is even simpler - 2 lights (power and access to the ATA controller) should be clearly visible and have the usual colors (power - yellow or green, access to the ATA controller - red).
How to choose a case
In my opinion, people who buy a computer for their home are divided into two categories: those who need a computer at home as an addition to work, and those for whom a home computer is a completely independent thing (often the only computer to which a person has access ). Accordingly, different requirements are put forward for enclosures - both in terms of design and expansion capabilities. One of the most important requirements is high hull strength. When purchasing, you should make sure that the side walls do not bend under light pressure. The recommended thickness of the case walls should be at least 0.8 mm, and the edges of the walls and frame should be carefully rolled so as not to cut your hands. To build a computer additional to a working one, I recommend providing external access compartments in the case for the following devices: drive optical disks(from CD-R to DVD), rack2 for ATA hard drives, Zip drive. As we can see, such a computer requires 3 external 5.25” bays, which corresponds to the midi-tower specification. However, it is worth thinking about the future and purchasing a case with not 3, but 4 compartments. As they say, the stock doesn't stretch your pocket. However, excessive stock is also not welcome, so when purchasing, you need to clearly understand which devices will be installed right now, and which can be added in a year or two.
For a home computer, as a rule, slightly different requirements are put forward. Thus, a larger number of connected peripheral devices(printer, scanner, etc.). In addition, the use of 3D accelerators increases the heat dissipation inside the case, and the use of devices connected via an interface card increases the load on the inside of the case with expansion cards and greatly complicates the cooling of electronic components. All of the above makes the use of desktop cases extremely difficult. From this point of view, it would be optimal to use midi-tower or tower cases.
Experience shows that buying a case with too many compartments for possible future expansion is not advisable (primarily from a financial point of view). For a work computer, it is quite enough to have 2 compartments in reserve with external access (3.5” and 5.25”), as well as 1-2 internal bays for hard drives. The most universal option seems to be the use of midi-tower cases, which have an optimal price/expansion capabilities ratio.
ComputerPress 4"2001
Operating system, installed programs, documents, photos, music and movies are stored on the hard drive. HDD capacity ( hard drive) is measured in Gigabytes. It is believed that the more, the better. As they say, there is never too much free space.
The front panel of the PC system unit usually contains two buttons:
- Power – used to turn on the computer;
- Reset - used when it is necessary to urgently restart the computer if it is frozen.
Also on the front panel you can find the following elements:
- indicators - LEDs and light bulbs that display the operation of the PC: indication of computer operation, indication hard state disk.
- floppy drives and optical drives are devices designed to work with storage media such as floppy disks and optical discs.
- connectors - designed to connect some external devices. Most often these are USB connectors, as well as a jack for connecting headphones and a microphone.
If you want to assemble a new system unit, if you want it to be made especially for you and not be like hundreds of others sold in stores, then the center computer help The site will be happy to help you make your dream come true. By contacting our service, you can be sure of the reliability and durability of your future computer. After all, its assembly and configuration will be carried out by professionals with many years of successful experience!
The topic of form factors and standard sizes was briefly touched upon in relation to the subject of discussion. Today let's take a closer look at the types of PC cases. Their types, sizes and characteristics are important to know for everyone who assembles a computer on their own.
Instead of a preface
As in many areas, computer equipment is subject to strict standardization and typing. This not only allows you to achieve the required operating parameters from certified components, but also allows you to assemble the necessary configuration from a wide range of devices presented on the market by various brands. 
Naturally, there is no ideal standard, just as there is no single “correct” case size. The types and their characteristics are aimed primarily at ease of use. Currently, there are 25 standard sizes of computer cases - both widely used and purely niche solutions.
From this article you will learn:
The latter are a subject of interest to narrowly specialized specialists, so they were not included in our description. All types will most likely be uninteresting to you, friends. And so, briefly and to the point.
Little known and rare
Monoblock
What it is? A computer consists of a system unit and a monitor assembled into a single whole. Unlike the types listed below, there are no clear niche standards for dimensions here, and everything is determined by the standards of the manufacturer.
The most famous of this category include Mac computers from Apple. Hotly loved by American users, this brand has hardly caught on here due to its exorbitant cost.
The advantages include the fact that such an assembly takes up minimal space. The disadvantages are that the upgrade options in this case are extremely limited: most likely, more powerful components simply will not fit in the case.
Rack
Niche solution: this case is used exclusively for mounting server and telecommunications equipment in 19-inch racks. The dimensions allow you to stuff any filling into such a case, including a pair of power supplies that duplicate each other’s work. 
Not suitable for home use: it is an open type case, not equipped with a lid. From above it is covered only by the bottom of the neighbor on the counter.
Barebone
A simplified solution from the manufacturer: a kit for quick PC assembly, based on pre-installed components. Variations are possible in terms of processor, hard drive and RAM characteristics. Replacing, for example, a motherboard, can already cause certain difficulties for the owner.
For home use, it is only suitable for users who are not concerned about performance issues and upgrades. At the same time, this is one of the best solutions for corporate users, allowing them to assemble the required number of working computers as quickly as possible. 
In one of the news I talked about a similar thing, you can take a look.
AT and Slim
The first is “dinosaur”, which is no longer used anywhere today. Appeared back in the days Intel processors 486 and was subsequently supplanted by more modern standard ATX. However, its logical development, in a slightly different direction, led to the emergence of such “mutants” as Slim and Ultraslim cases - thin and ultra-thin, respectively. 
Yes, the thin “turret” looks stylish and unusual, but in terms of characteristics, such an assembly is completely “zero” - it is physically impossible to install more or less powerful components here.
Horizontal
In our country, this type of case is not very popular among users, but in Western countries it has become widespread. The advantage is that this configuration takes up a little less space: the monitor can be placed directly on the system unit.
The most popular types would be:
- Desktop (desktop) – 533x419x152 mm;
- FootPrint (floor) – 408x406x152 mm;
- SlimLine (thin) – 406x406x101 mm;
- UltraSlimLine (ultrathin) 381x352x75 mm.
Vertical
Due to their position in space, such buildings are called towers. There is an opinion that due to the peculiarities of the layout of the parts, such a system unit is cooled better inside.
By purpose, here you can find options for all occasions: from server solutions to “babies” that are only suitable as a typewriter. Let's look at our most popular vertical ATX cases.
Full Tower
The full tower is up to 20 cm wide, up to 60 cm high and up to 1 m long. It can have from 4 to 9 5.25-inch bays (under optical drive), from 6 to 12 3.5-inch bays (for hard drive). Allows you to install up to seven expansion cards - for example, a sound card or receiver. 
Accommodates a full-size ATX motherboard. On the basis of such a case you can assemble both a powerful gaming computer and a small one. local server– there is enough space for all sorts of hardware.
Big Tower
The large tower has clearly regulated dimensions - 190x482x820 mm. It also allows you to install a full-size system board ATX, however, there is less space for filling. 
Can be used to build a powerful gaming computer.
Midi Tower
The middle tower has dimensions of 183x432x490 and is perhaps our most popular type of computer case. 
Accommodates an ATX board and matching power supply, multiple hard drives. It is considered a universal option: on the basis of such a case you can build a low-power office computer, a home media center, and a gaming computer.
Mini Tower
The mini tower has dimensions of 178x432x432. It is unlikely that it will be possible to cram powerful components here, so this option is more suitable for a work computer or home theater, taking up little space. 
And the smallest type, Micro Tower, has even more compact dimensions and is used to assemble the lowest-performance computers, in which all the peripherals are integrated into the motherboard.
How to determine your computer case type? - you ask. It’s very simple - measure its dimensions with a tape measure and correlate the data with the above standards.
I also advise you to read the publication about. And if you don’t know for a computer, take a look at this - huge store, the assortment will pleasantly shock you.