What's the function of those PC computer cases? What's in

What's the function of those PC computer cases? What's in them? Why?

PC computer cases contain the parts that make up the computer, excluding such devices as the keyboard and monitor. All cases house the computer's motherboard, the board on which circuits have been laid out between various sockets and components that comprise the computer, such as the central processing unit, ISA, PCI and AGP components, and computer memory. PCs generate heat, so PC computer cases will also house a fan. PC's run off of electricity, so the case also houses a power supply case. The primary function of PC computer cases is to securely house the computer's components.

Most PC computer cases are rectangular in shape. The case is founded on a frame to which is attached bottom, top and side panels. Normally, the bottom panel is not designed to be removed. Attached to each corner of the bottom panel are rubber feet, used to keep the computer from sliding about. Usually, both side panels may be removed to allow access to the internals, but the front and back panels remain stationary.

The back panel has several holes to accommodate the connection of devices, such as the keyboard, mouse, monitor and speakers. Usually, the case has long, rectangular holes covered by metal pieces called face plates, that may be removed, from the inside. If you install a component that requires connection to some external device, such as a video card used for TV reception, the component you install will need to have its connectors exposed to the outside. That is the purpose of these long holes, permitting you to install a board that connects to external devices. There is also a hole that exposes the power supply connection. A grated, circular hole in the back panel enables the fan inside to draw, or vent air. There may also be numerous small holes, used for ventilation.

The front panel of PC computer cases normally contains the power button you press to turn on the computer, and drive bays that allow access to disk drives, such as floppy, CD or DVD disk drives. There may also be an LED indicator, a light, that indicates that the computer is on, but may also be used to indicate hard disk operation. Most new cases also have USB connectors in which you may plug in such devices as a mouse or external speakers.

Some PC computer cases have top panels, with a well in which you can store CDs. Otherwise, the top panel primarily serves for protection. Although sturdy, the top of your computer should not be used to support other things. As well as decreasing air flow around the computer, things stored on the top of a computer often fall because the top is somewhat rounded.

Housing a computer's components is the most obvious purpose of PC computer cases, but there is more to this than meets the eye. Most cases are made of metal or hard plastic. These materials offer sturdy protection of the computer's internals. Additionally, the material protects people. The shock you'd get by laying your hand on an exposed motherboard or a capacitor explains how these cases protect you against the dangers that lurk within.

PC computer cases also have an internal architecture. The case contains an area to which the motherboard is mounted, as well as a mount for the power supply box. Normally, a power supply box comes with its own fan. A case, however, may provide a mount for an auxiliary fan. The case will also have racks for mounting your internal hard drives and perhaps a mount for the internal speaker.

PC computer cases are designed for optimum cooling of the internals. Never block the case's ventilation holes.

PC computer cases vary in size and layout. Standard case dimensions and layouts have evolved along with the PC, as the internals of the PC, especially the motherboard, have evolved. Naturally, the case must be able to accommodate its components. A specific dimension and layout is called a form factor. The first PC computer cases were made by IBM for its PC and PC/XT models. Appropriately, these very large cases form factor is PC/XT. In 1984, IBM produced the PC/AT, giving rise to the AT form factor. Although the AT had a larger power supply and the motherboard was in a different position, the PC/XT and AT form factors were similar. Shortly after the AT came out, a smaller case was introduced, called the Baby AT. It was simply a smaller case, taking up less room on a desk. The Baby AT form factor, as its predecessor, stood on the narrow side of the box. Its successors, the LPX and mini LPX, stood on its wide side. Many people set their monitor on top of an LPX, reducing desk space usage. Intel then came up with the NLX form factor, which was similar to the LPX, but stood the case back up on its narrow side. With a new motherboard, the AT form factor was superseded by the ATX, the mini-ATX and the extended ATX form factors, which were then replaced by the microATX and FlexATX form factors. In all cases, the change in form factors followed changes in component dimensions. Most modern PC computer cases, also called system cases, are variants of the ATX, each striving for a smaller footprint than its predecessor. With the advent of more powerful computer components, the WTX or workstation form factor has been added to the mix.

Finally, cases are also objects in our home and work space. Manufacturers attempt to create PC computer cases that are visually appealing. Sometimes, the addition of color alone increases the price. When purchasing a system case, let the aesthetic appeal be your least considered point. You'll save money!