Computer case
Encyclopedia
A computer case is the enclosure that contains most of the components of a computer
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

 (usually excluding the display, keyboard and mouse). A computer case is sometimes incorrectly referred to metonymously as a CPU or hard drive referring to components housed within the case. CPU was a more common term in the earlier days of home computers, when peripheral
Peripheral
A peripheral is a device attached to a host computer, but not part of it, and is more or less dependent on the host. It expands the host's capabilities, but does not form part of the core computer architecture....

s other than the motherboard were usually housed in their own separate cases.

Cases are usually constructed from steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 (often SECC — Steel, Electrogalvanized, Cold rolled, Coil) or aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....

. Plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

 is sometimes used, and other materials such as wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

 and even Lego
Lego
Lego is a line of construction toys manufactured by the Lego Group, a privately held company based in Billund, Denmark. The company's flagship product, Lego, consists of colorful interlocking plastic bricks and an accompanying array of gears, minifigures and various other parts...

 blocks have appeared in home-built cases.

Sizes

Cases can come in many different sizes (known as form factors). The size and shape of a computer case is usually determined by the form factor of the motherboard
Motherboard
In personal computers, a motherboard is the central printed circuit board in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals. The motherboard is sometimes alternatively known as the mainboard, system board, or, on Apple...

, since it is the largest component of most computers. Consequently, personal computer form factors typically specify only the internal dimensions and layout of the case. Form factors for rack-mounted and blade
Blade server
A blade server is a stripped down server computer with a modular design optimized to minimize the use of physical space and energy. Whereas a standard rack-mount server can function with a power cord and network cable, blade servers have many components removed to save space, minimize power...

 server
Server (computing)
In the context of client-server architecture, a server is a computer program running to serve the requests of other programs, the "clients". Thus, the "server" performs some computational task on behalf of "clients"...

s may include precise external dimensions as well, since these cases must themselves fit in specific enclosures.

For example, a case designed for an ATX
ATX
ATX is a motherboard form factor specification developed by Intel in 1995 to improve on previous de facto standards like the AT form factor. It was the first big change in computer case, motherboard, and power supply design in many years, improving standardization and interchangeability of parts...

 motherboard and power supply may take on several external forms, such as a vertical tower (designed to sit on the floor, height > width) or a flat desktop (height < width) or pizza box
Pizza box form factor
In computing, a pizza box is a style of case for computers or network switches. Cases of this type tend to be wide and flat, normally one or two rack units in height, thus resembling pizza delivery boxes....

(height ≤ 2 inches, designed to sit on the desk under the computer's monitor). Full-size tower cases are typically larger in volume than desktop cases, with more room for drive bay
Drive bay
A drive bay is a standard-sized area for adding hardware to a computer. Most drive bays are fixed to the inside of a case, but some can be removed....

s and expansion slots. Desktop cases—and mini-tower cases designed for the reduced microATX
MicroATX
microATX, also known as µATX is a standard for motherboards that was introduced in December 1997. The maximum size of a microATX motherboard is 244 mm × 244 mm , but some microATX boards can be as small as 171.45 mm × 171.45 mm...

 form factor—are popular in business environments where space is at a premium.

Currently, the most popular form factor for desktop computers is ATX, although microATX and small form factor
Small form factor
A small form factor is a computer form factor designed to minimize the volume of a desktop computer. For comparison purposes, the size of an SFF case is usually measured in litres. SFFs are available in a variety of sizes and shapes, including shoeboxes, cubes, and book-sized PCs...

s have also become very popular for a variety of uses. Companies like In Win Development
In Win Development
In Win Development is a public company in Taiwan. Its reginal offices are located in US, UK, Netherlands and China. The main product lines include computer case, power supply, rackmount and tower servers and computer storages peripheral...

, Shuttle Inc.
Shuttle Inc.
Shuttle is a Taiwan-based manufacturer of motherboards, barebone computers, complete PC systems, and monitors. Throughout the last 10 years, Shuttle has been one of the world's top 10 motherboard manufacturers, and gained fame in 2001 with the introduction of the Shuttle SV24, one of the world's...

 and AOpen
Acer (company)
Acer Incorporated is a multinational information technology and electronics corporation headquartered in Xizhi, New Taipei City, Taiwan. Acer's products include desktop and laptop PCs, tablet computers, servers, storage devices, displays, smartphones and peripherals...

 have popularized small cases, for which FlexATX
FlexATX
FlexATX is a motherboard form factor derived from ATX. The specification was released in 1999 by Intel as an addendum to the microATX specification...

 is the most common motherboard size. Apple Inc. has also produced the Mac Mini
Mac Mini
The Mac Mini is a small form factor desktop computer manufactured by Apple Inc. Like earlier mini-ITX PC designs, it is uncommonly small for a desktop computer: 7.7 inches square and 1.4 inches tall. It weighs 2.7 pounds...

 computer, which is similar in size to a standard CD-ROM drive.

Tower cases come in mini-tower, mid-tower, and big-tower/full-tower sizes. Full tower cases are typically 22 inches or more in height and intended to stand on the floor. They have anywhere from six to ten externally accessible drive bays, with more bays only internally accessible. The ratio of external to internal bays is shifting, however, as computing technology moves from floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...

s and CD-ROM
CD-ROM
A CD-ROM is a pre-pressed compact disc that contains data accessible to, but not writable by, a computer for data storage and music playback. The 1985 “Yellow Book” standard developed by Sony and Philips adapted the format to hold any form of binary data....

s to large capacity hard drives, USB flash drives, and network-based solutions. Midtower cases are smaller, about 18" high with two to four external bays. A minitower case will typically have only one or two external bays and stand from 14" to 16" tall.

Layout

Computer cases usually include sheet metal enclosures for a power supply unit and drive bays, as well as a rear panel that can accommodate peripheral
Peripheral
A peripheral is a device attached to a host computer, but not part of it, and is more or less dependent on the host. It expands the host's capabilities, but does not form part of the core computer architecture....

 connectors protruding from the motherboard and expansion slots. Most cases also have a power button or switch, a reset button
Reset button
In electronics and technology, a reset button is a button that can reset a device. On video game consoles, the reset button restarts the game, losing the player's unsaved progress. On personal computersOn IBM mainframes reset neither clears memory nor initiates an IPL., the reset button clears the...

, and LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

s to indicate power status as well as hard drive and network activity. Some cases include built-in I/O ports (such as USB and headphone ports) on the front of the case. Such a case will also include the wires needed to connect these ports, switches and indicators to the motherboard.

Major component locations

  • The motherboard
    Motherboard
    In personal computers, a motherboard is the central printed circuit board in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals. The motherboard is sometimes alternatively known as the mainboard, system board, or, on Apple...

     is usually screwed to the case along its largest face, which could be the bottom or the side of the case depending on the form factor and orientation.
  • Form factors such as ATX
    ATX
    ATX is a motherboard form factor specification developed by Intel in 1995 to improve on previous de facto standards like the AT form factor. It was the first big change in computer case, motherboard, and power supply design in many years, improving standardization and interchangeability of parts...

     provide a back panel with cut-out holes to expose I/O ports provided by integrated peripherals, as well as expansion slots which may optionally expose additional ports provided by expansion card
    Expansion card
    The expansion card in computing is a printed circuit board that can be inserted into an expansion slot of a computer motherboard or backplane to add functionality to a computer system via the expansion bus.One edge of the expansion card holds the contacts that fit exactly into the slot...

    s.
  • The power supply unit is often housed at the top rear of the case; it is usually attached with four screw
    Screw
    A screw, or bolt, is a type of fastener characterized by a helical ridge, known as an external thread or just thread, wrapped around a cylinder. Some screw threads are designed to mate with a complementary thread, known as an internal thread, often in the form of a nut or an object that has the...

    s to support its weight.
  • Most cases include drive bay
    Drive bay
    A drive bay is a standard-sized area for adding hardware to a computer. Most drive bays are fixed to the inside of a case, but some can be removed....

    s on the front of the case; a typical ATX case includes both 5.25" and 3.5" bays. In modern computers, the former are used mainly for optical drives, while the latter are used for hard drives, floppy drives, and card reader
    Card reader
    A card reader is a data input device that reads data from a card-shaped storage medium. Historically, paper or cardboard punched cards were used throughout the first several decades of the computer industry to store information and programs for computer system, and were read by punched card readers...

    s.
  • Buttons and LEDs are typically located on the front of the case; some cases include additional I/O ports, temperature and/or processor speed monitors in the same area.
  • Vents are often found on the front, back, and sometimes on the side of the case to allow cooling fans
    Computer fan
    A computer fan is any fan inside, or attached to, a computer case used for cooling purposes, and may refer to fans that draw cooler air into the case from the outside, expel warm air from inside, or move air across a heatsink to cool a particular component...

     to be mounted via surrounding threaded screw holes.

Internal access

Tower cases have either a single side panel which may be removed in order to access the internal components or a large cover that saddles the chassis. Traditionally, most computer cases required screws
Computer case screws
Computer case screws are the hardware used to fasten together parts of a computer case and to fasten the system components to the case. Although there are numerous manufacturers of computer cases throughout the world, the computer industry has generally standardized on some specific screw thread...

 to hold components and panels in place (i.e. motherboard, PSU, drives, and expansion cards). Recently there is a trend toward "screwless" cases, in which components are held together with snap-in plastic rails, thumbscrews, and other methods that do not require tools; this facilitates quick assembly and modification of computer hardware.

Appearance

Through the 1990s, most computer cases had simple rectangular shapes, and were often painted beige
Beige
Beige may be described as an off tan color or an extremely pale brown color.The term originates from beige cloth, a cotton fabric left undyed in its natural color...

 or white
White
White is a color, the perception of which is evoked by light that stimulates all three types of color sensitive cone cells in the human eye in nearly equal amounts and with high brightness compared to the surroundings. A white visual stimulation will be void of hue and grayness.White light can be...

 with little attention given to visual design. Beige box
Beige box
In consumer computer products, a beige box is a standard personal computer . It has come to be used as a term of derision implying conservative or dated aesthetics and unremarkable specifications....

 designs are still found on a large number of budget computers assembled from generic components. This class of machines is still known as white box computers
White box (computer hardware)
In computer hardware, a white box is a personal computer or server without a registered brand name. For instance, the term is applied to systems assembled by small system integrators and to homebuilt computer systems assembled by end users from parts purchased separately at retail. In this latter...

.

Case modding is the artistic styling of computer cases, often to draw attention to the use of advanced or unusual components. Since the early 2000s, some cases have included clear side panels or acrylic windows so that users can look inside while it is operating. Modded cases may also include internal lighting, custom paint, or liquid cooling system
Watercooling
Water cooling is a method of heat removal from components and industrial equipment. As opposed to air cooling, water is used as the heat conductor. Water cooling is commonly used for cooling automobile internal combustion engines and large industrial facilities such as steam electric power plants,...

s. Some hobbyists build custom cases from raw materials like aluminum, steel, styrofoam, acrylic, or wood.

Case manufacturers

Prominent after-market
After-market (general)
After-market refers to any market where the customers who purchase one product or service are likely to purchase a related, follow-on product....

 case manufacturers include Ahanix, AeroCool, Antec
Antec
Antec, Inc. is an American-based maker of PC components and accessories. Antec's principal products are computer cases and power supplies. Antec also offers PC cooling products and notebook accessories. Founded in 1986, the company is headquartered in Fremont, California, U.S.A., with additional...

, AOpen
AOpen
AOpen is a major electronics manufacturer from Taiwan that makes computers and parts for computers. AOpen used to be the Open System Business Unit of Acer Computer Inc. which designed, manufactured and sold computer components. It incorporated in December 1996 as a subsidiary of Acer Group with an...

, Asus
ASUS
ASUSTeK Computer Incorporated is a multinational computer technology and consumer electronics product manufacturer headquartered in Taipei, Taiwan. Its product range includes motherboards, desktops, laptops, monitors, tablet PCs, servers and mobile phones...

, Chenbro, Chieftec
Chieftec
Chieftec Industrial Co., Ltd. is a company established in 1990 that manufacturers computer cases and computer power supply units.The company's headquarters is in Taiwan, but has production facilities in Kwangtung and Zhejiang in mainland China....

, Ci Design, Cooler Master
Cooler Master
Cooler Master is a computer hardware manufacturer from Taiwan. Founded in 1992, the company is a popular aftermarket brand for computer chassis, PSU, coolers, cooling pads, and other accessories...

, Ever Case, Foxconn
Foxconn
The Foxconn Technology Group is a multinational business group anchored by the Hon Hai Precision Industry Co., Ltd. , a Taiwan-registered corporation headquartered in Tucheng, Taiwan...

, Gigabyte Technology
Gigabyte Technology
Gigabyte Technology Co., Ltd. is a Taiwan-based manufacturer of computer hardware products best known for its motherboards. The company is publicly held and traded on the Taiwan Stock Exchange .-Company:...

, HEC Compucase, In Win Development
In Win Development
In Win Development is a public company in Taiwan. Its reginal offices are located in US, UK, Netherlands and China. The main product lines include computer case, power supply, rackmount and tower servers and computer storages peripheral...

, IXIUM
IXIUM
IXIUM is a company established in 2004 that manufactures computer cases marketed for gamers.- See also :*Antec*Chieftec*Lian Li*SilverStone Technology*Thermaltake*Zalman...

, Lian Li
Lian Li
Lian Li Industrial Co., Ltd. is a Taiwanese computer case and accessories manufacturer...

, Lin Chi, CIRCLE
Circle
A circle is a simple shape of Euclidean geometry consisting of those points in a plane that are a given distance from a given point, the centre. The distance between any of the points and the centre is called the radius....

, FRONTECH, ODYSSEY
Odyssey
The Odyssey is one of two major ancient Greek epic poems attributed to Homer. It is, in part, a sequel to the Iliad, the other work ascribed to Homer. The poem is fundamental to the modern Western canon, and is the second—the Iliad being the first—extant work of Western literature...

, ZEBRONICS, NZXT, OrigenAE, Raidmax
RAIDMax
Raidmax and its parent company Raidcom Technologies is a manufacturer of computer cases, computer power supplies, and CPU coolers for personal computers. Their headquarters is located in California, but their manufacturing and design is done in Taiwan. Their primary intention was to become the...

, Shuttle Inc.
Shuttle Inc.
Shuttle is a Taiwan-based manufacturer of motherboards, barebone computers, complete PC systems, and monitors. Throughout the last 10 years, Shuttle has been one of the world's top 10 motherboard manufacturers, and gained fame in 2001 with the introduction of the Shuttle SV24, one of the world's...

, SilverStone Technology
SilverStone Technology
SilverStone Technology is a company based in Taiwan that makes computer cases, power supplies, and other peripheral for personal computers. The company SilverStonetek Co Ltd was founded in 2003....

, Thermaltake
Thermaltake
Thermaltake is a manufacturer of PC cases, power supplies and cooling solutions. Its main headquarters is located in Taipei and Thermaltake has multiple manufacturing facilities on mainland China, including a major plant at Dongguan which is also ISO-9001 certified.Most of Thermaltake's production...

, Xclio, Yue Lin, and Zalman
Zalman
Zalman Tech Co. is a Korean company that develops and provides aftermarket desktop computer products with primary focus on cooling enhancement....

.

Intrusion detection

Some computer cases include a biased switch (push-button) which connects to the motherboard. When the case is opened, the switch position changes and the system records this change. The system's firmware
Firmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...

 or BIOS
BIOS
In IBM PC compatible computers, the basic input/output system , also known as the System BIOS or ROM BIOS , is a de facto standard defining a firmware interface....

 may be configured to report this event the next time it is powered on.

This physical intrusion detection
Intrusion detection
In Information Security, intrusion detection is the act of detecting actions that attempt to compromise the confidentiality, integrity or availability of a resource. When Intrusion detection takes a preventive measure without direct human intervention, then it becomes an Intrusion-prevention...

 system may help computer owners detect tampering with their computer. However, most such systems are quite simple in construction; a knowledgeable intruder can open the case or modify its contents without triggering the switch.

See also

  • Computer case screws
    Computer case screws
    Computer case screws are the hardware used to fasten together parts of a computer case and to fasten the system components to the case. Although there are numerous manufacturers of computer cases throughout the world, the computer industry has generally standardized on some specific screw thread...

  • List of computer hardware manufacturers
  • Thermally Advantaged Chassis
    Thermally Advantaged Chassis
    a thermally advantaged chassis is a computer enclosure that is capable of maintaining an internal ambient temperature below 38 degrees Celsius when functioning with Intel's Pentium 4 and Celeron D processors based on 90 nm process technology, and an ambient temperature below 39 degrees Celsius when...


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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