how computer cases work
Post on 14-Oct-2014
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How Computer Cases Work Written by Matthew Elton (copyright 2006 Matthew Elton)
This is a picture of an ATX size case. This is the standard size for most computers. It is made to hold the ATX size motherboard.
Okay, so you might not consider the case one of the key parts of the computer, but it is actually very important.
The case doesnt do any actual computing like the most of the other parts of the computer do, but it is still very important because it protects all of the electronic components inside and provides adequate ventilation to prevent overheating. A good case is small enough to fit where you want it to go, but large enough so that theres some extra space inside so you can add new hardware if you want. Some cases have only a couple expansion bays.
This may not be enough if you plan to add a lot of drives to your computer. There also should be several expansion slots on the back for adding expansion cards. There are several different case sizes, each made to hold different size motherboards. Most computers have the ATX size case and ATX size motherboard. There is also a smaller microATX case that is used with the slightly smaller microATX motherboard. Before the ATX case was invented, there was an AT case for the older AT type motherboards. Many modern cases are made so that ATX, microATX, and even the older AT type motherboards securely fit in them. The smallest type of desktop case lies flat, so a monitor can be placed on top of it. Other cases stand upright, like the Mid-ATX case shown in the picture below:
This picture shows the front panel of the Mid-ATX size case, with two external 3.5-inch drives expansion bays and four external 5.25-inches drive expansion bays. Most front panels have an on/off switch, as well as a reset switch that can be used to restart the computer when it freezes. Most front panels also have a power light and a hard drive activity light. Case speakers are usually located just behind the front panel. Most computers just have an internal system speaker, which only makes one or two different tones. However, some computers have a full sound speaker inside of
them, usually attached to the front panel of the case. Some front panels also have USB, audio serial, and/or game ports in the front panel to make them easy to access.
This picture shows the back panel of a computer case. In this picture above you can see that there are a lot of openings on the back of a computer case. On the left are the motherboard input/output (I/O) ports. In the top lefthand corner you can see where the power cord plugs into the power supply. Below that is an on/off switch built into the power supply. Not all power supplies have these switches. Between the power switch and the spot where the power plug plugs in, is a small switch that allows you to select different voltage types, since different countries use different voltages for their power outlets. To the right of the on/off switch and power plug input is the power supplys fan, which prevents the power supply from overheating. The small holes on the right side allow air to circulate throughout the case, to prevent the computer from overheating. An optional case fan, for increased air circulation, can be placed here. Near the bottom, on the left-hand side of the case rear panel, are seven expansion slot covers. The metal strips can be removed expansion slot cards can go in their place.
This is a picture of an internal motherboard system speaker, which attaches to the inside of the computer case. The wire plugs into the motherboard. You seldom here the case speaker, since most sound is produced from external speakers (although some computers have internal sound speakers and no external speakers). Sometimes, however, you might hear a warning or error beep from the system speaker, especially when using BIOS.