The Body of the computer is delivered with built-in power supply unit (he works out the different voltages for internal device and system charge). Following types body are used For home computer:

1. AT
2. ATX

The Difference in specifics of the connection power supply unit and maternal charge in following: ATH allows management a power supply unit software with maternal charge. The New types of the feeding (after AT) are developed company Intel coming from need of the development computer, particularly system charges. Herewith transition was taken into account on lowered voltages, improvement of the mutual location internal component, as well as refusal of outdated buses and port.

From type of the body of the computer and superblock depends, in particular, sizes, order of the accomodation and amount used component of the computer, as well as minimum power power supply unit. Usually body has a form of the parallelepiped moreover with two brightly expressed greater verge. Depending on that, are located these galley proof horizontally or in on-position vertically, body divide on two greater classes.

Desktop (desktop (533x419x152)). Bukvalinyy translation - desk. The Body is put on table by big verge.
The Tower (tower). The Greater galley proof are located vertically.

Desktop appeared first, but presently he has obviously grown old on the following considerations. Earlier display had a small size (with screen 14" and 15") and their put on десктоп for spare place on table. But if put(deliver) on десктоп - a body modern big (17" and 19") display, that break the комфортное location an eye. This is because user must look at screen little from top to bottom. Exactly, upper edge of the screen must be on several centimetres below level eye, but screen itself is turned perpendicular взору. It Is Explained this that that ages must be полузакрыты, otherwise occurs высыхание ocular влаги. Not for nothing in some computer tables stand for display do lowerring downwards and having slope. The Accomodation of such body and display apart requires too much places. Besides, uncomfortably remove the heavy display (and herewith else find the place, where his(its) put(deliver)) as required open the body, десктоп possible put(deliver) and on side, having transformed him(it) in tower, but such change will not be full-fledged. First, is obstructed opening the body. Secondly, not all drives orderly works with withdrawable disk in vertical position. For compact disk it happens to to turn holding their petal that also complicates functioning.

The Towers are divided on four subranges, differring on height. In order of the growth this - micro (micro), mini (mini - 152x432x432), миди (midi, middle - 173x432x490) and full (big, full - 190x482x820). For majority body "qualifier" is a number greater external compartment, according to brought below table (though be and exceptions).

Type to towers	Number greater compartment
Full	4-8
Midi	3
Mini	2
Micro	1

The Body has certain number greater (5.25") and small (3.5") external compartment (bay, is read bay), leaving to card face. In they are inserted that internal device, to which is required access in process of the work: drives of the diskettes (флоповод) and компакт disk. Under traditional design compartments are situated overhand moreover greater above small.

Optimalinosti midi towers

The Full tower is intended for server, and bulky (on height), surplus and road for home computer. The Full towers usually have a door, closing compartments and buttons.

The Micro tower has an insufficient number compartment. Besides, a deal bad is in micro body with tap of the heat. The Spare heat extremely disadvantage acts on all without exception internal components. So the most popular mini and миди towers. Midi tower with her(its) large number compartment more preferred.

Besides, only body миди towers possible completely to barrier 17'' display from bright lateral light (the heights mini to towers for this it is not enough). Thereby, миди tower is a good compromise between expandability and compactness.

Number small compartment

Aside from amount greater medicine to be taken externally compartment (which define the type to towers) beside body there is else such parameters:

• small (3.5'') medicine to be taken externally
• small (3.5'') internal

The Number small medicine to be taken externally compartment usually is 1 or 2. One compartment at present nearly always occupied under флоповод, since industry azh with 1984 can not move to more capacious drive (to the extent that that no industry-standard). The Second compartment can, for instance, be useful for:

• the drive of the diskettes to high capacity (the type Zip or iOmega);
• the concentrator port USB. He suitable, when it is necessary often to connect the external device with USB interface;
• IK-transmitter (инфро red). It Is Used, for instance, for work with printer.

The Number small internal compartment usually also is 1 or 2. They are used for installing hard disk. For integer of expandability also advisable to their was 2. For instance, at seizure video sometimes array from 2-4 hard disks.

Advantage ATX before AT

ATX is decipherred as AT eXtension (the expansion AT) and is a specification to companies Intel on body and system charge (the specification has several issues). Further in detail advantage are considered over AT.

 

Expansion of the possibilities power supply unit

The Components of the system charge use the voltage as 5 В, so and 3.3 V. In standard AT on charge is given only 5 В, but 3.3 In is got by converter of the voltage on this charge. In ATX voltage 3.3 In is worked out power supply unit itself so need in converter on charge falls off. This frees the place on charge and perfects the heat mode. For flexible management mode "VWVappear in the dreams" with possibility "awakening" from keyboard, the bell on modem and the other event is provided constant presenting on system charge of the voltage. If body is executed according to full specification, that power supply unit has on rear of the body separate breaker, allowing обесточить system charge. Opcionalino possible control velocity ventilator, warm-up checking power supply unit and checking the value of the voltage 3.3 volt.

Direction of the airstream

Housed AT ventilator power supply unit always выдувает the flow (from back part). In initial specification of the body ATX was provided soaking up the air to direct the flow on processor. This allows in general to abandon to own кулера on processor, replaceable his(its) big radiator. Now нестрашно if noiseless кулер will suddenly refuse, and processor перегреется and come out of building. This decision really ingenious for десктопов. The удобнее turned out to be For tower as before выдувать air that perfects теплообмен. This is because, first, power supply unit itself warms the air, secondly, warm air rises upstairs. Hereinafter power supply unit itself comfortable to place on system charge and even on ledge. So he anymore blows on the system charge. А for обдува processor is used additional ventilator.

Connectors port are stood on main charge

The Connectors port, leaving on back part of body, are located on most main to charge. Beside charges of the format AT they are situated on bracket, to which lead the connecting cables. As a result improves the ventilation of the charge and is simplified montage. On this sign easy to distinguish the body ATX from AT: behind connectors housed tower are located not horizontal rows, but vertical (in Desktop - on the contrary).

Hereinafter, unlike AT, where system charge bears up to body plastic drumstick, in ATX are used screws that adds reliability (however, this in ideal - in practice system charge and in ATH-body quite often bear up with the help of plastic drumstick).

Power supply unit

Exists several standard importances of the power. 200 Will suit For home computer, 235, 250 and 300 Vt moreover for ATX body typical two last importances. We shall Notice that, in spite of forecasts of the reduction энергопотребления, modern высокооборотные hard disks and graphic boosters sooner raise the plank. Too pertains and to магнитооптике. Since useful have a spare on powers, that is recommended power 300 Vt. (For function suspend to RAM needs the big current (720 ma otherwise memory does not подпитаешь)). Such current gives Elan 10AB (750). see So big power will not disturb.

The Power supply unit in tower dispose in higher part of the body usually, but below his(its) is situated the system charge. In it is enough high body power supply unit is situated on system charge completely so their projections on lateral wall are not crossed. This is an usual location, "without overlapping". In more low body (39 refer to and below) specified projections are partly crossed, since power supply unit was gone on to 90 for longitudal axis. So such body several broader usual - an order 22 refer to On system charge under power supply unit is found jack of the processor. This creates the following inconvenience:

• processor locked power supply unit and so for work with processor it is necessary first to unmount power supply unit (or lead work blindfold)
• power supply unit clutters up place beside processor, worsenning his(its) thought over
• appears the restriction on height of the connecting charges for processor (сокетный variant for слотового jack). To avoid this, company ASUS releases the special низкопрофильные of the connecting charge.

Funkcionalinosti body

The Leaving lateral wall (left if look on the part of person) provides the light access to internal component. Both sides leave Beside some body (then for acerbity upper wall usually forms one integer with carriage). In traditional performance cover is P-figurative. For quick removing (the cover or walls) instead of traditional screw use the screws with head in notch (the lamb) or lock-защелки. This allows to dispense in general without screwdriver. In some body use also leaving frame, on which takes seats the plate with system charge. All got up in charge to take out no need, including cards. However need of the unhooking from charge wiring indicator, as well as tumbling of the body (if he придвинут butt ends to wall) reduces attractiveness of this decision.

Design of the buttons of management

On card face are found as minimum 2 buttons: cut-in (POWER) and rebooting (RESET, unset). To their design are presented determined requirements (for instance, quite bad if all of these alike, for instance, round, one diameter and colour and are located close friend from friend.

The Requirements to button of the cut-in:

• must stand out colour and size from others
• must not emerge, better, when she is a little sunk (so she less is damaged and her(its) harder accidentally press)

For power supply the body of the type AT best breaker is a tumbler. For power supply the type ATX this in principle impossible since is it here measured also duration of the striking (developed BIOS are programmed on emergency de-energization when striking more than 4 seconds, when main button does not operate)

Button of the rebooting (Reset)

This button must be small and drowned to obstruct undeliberate striking on it. The Best variant, when she so small that is pressed only by fine subject of the type of the ball-point pen.

Filter for choice of the models

Below happen to the models ATX миди body (i.e. with 3 greater external compartments), and answerring following requirements:

• from thick steels
• with сертифицированным power supply unit, power not less 235 Vt, with operated a velocity of the rotation of the ventilator
• without overlapping of the system charge power supply unit
• with revenge for installing the additional ventilator
• with certificate FCC Class B on radiation
• with smooths processed edge
• with withdrawable lateral wall
• length not more than 47 with

Author: А. V. Savin It Is Added: 29.04.2007