Product Code Database
A computer case, also known as a computer chassis, is the enclosure that contains most of the hardware of a personal computer. The components housed inside the case (such as the CPU, motherboard, computer memory, mass storage devices, power supply unit and various ) are referred as the internal hardware, while hardware outside the case (typically electrical cable-linked or plug-and-play devices such as the computer monitor, computer speaker, keyboard, computer mouse and USB flash drives) are known as .
Conventional computer cases are fully enclosed, with small holes (mostly in the back panel) that allow ventilation and cutout openings that provide access to plugs/sockets (back) and removable media (front). The structural frame (chassis) of a case is usually constructed from rigid such as steel (often SECC — steel, electrogalvanized, cold-rolled, coil) and aluminium alloy, with and for mounting internal hardware, computer fan/coolers and for organizing cable management. The external case panels, at least one of which are removable, cover the chassis from the front, sides and top to shield the internal components from physical intrusion and dust collection, and are typically made from painted metallic and/or plastic material, while other materials such as mesh, tempered glass, acrylic, wood and even Lego bricks have appeared in many modern commercial or case modding. In recent years, open frame or open air cases that are only partly enclosed (with freer ventilation and thus theoretically better computer cooling) have become available in the premium gaming PC market.
For example, a case designed for an ATX motherboard and power supply unit (PSU) may take on several external forms such as a vertical computer tower (designed to sit on the floor, height > width), a flat Desktop computer (height < width) or pizza box (height ≤ ) designed to sit on the desk under the computer's computer monitor). Full-size tower cases are typically larger in volume than desktop cases, with more room for , , and custom or all-in-one (AIO) water cooling solutions. Desktop cases—and mini-tower cases under about high—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 factors have also become very popular for a variety of uses. In the high-end segment, the unofficial and loosely defined XL-ATX specification appeared around 2009. It extends the length of the mainboard to accommodate four graphics cards with dual-slot coolers. Some XL-ATX mainboards increase the mainboard's width as well, to allow more space for the CPU, Memory PWM, and in some cases, a second CPU socket. While the market share of these exotic high-end mainboards is very low, almost all high-end cases and many mainstream cases support XL-ATX (10 expansion slots). As of 2018, no major motherboard manufacturer has made an XL-ATX board for several years. E-ATX is similar to XL-ATX in that it is larger than ATX and is also loosely defined. Unlike XL-ATX, E-ATX motherboards and cases are still in production (as of 2020), and support quad-channel memory across 8 slots of ram, up to 4 PCI-e expansion slots for up to 4 double slot graphics cards and a single CPU such as the AMD Ryzen Threadripper 3990X. Companies like In Win Development, Shuttle Inc. and AOpen originally popularized small cases, for which FlexATX was the most common motherboard size. As of 2010 Mini ITX has widely replaced FlexATX as the most common small form factor mainboard standard. The latest mini ITX mainboards from Asus, Gigabyte, MSI, ASRock, Zotac and Foxconn offer the same feature set as full size mainboards. High-end mini ITX mainboards support standard desktop CPUs, use standard memory DIMM sockets, and mostly feature a full-size PCI-E 16× slot with support for the fastest graphics cards, although some instead use a PCI, or PCIe slot of fewer than 16 lanes. This allows customers to build a fully-fledged high-end computer in a significantly smaller case. Apple Inc. has also produced the Mac Mini computer, which is similar in size to a standard CD-ROM drive, and many manufacturers offer mini-ITX cases of similar size for low-wattage CPUs with integrated graphics.
Tower cases are often categorized as mini-tower, midi-tower, mid-tower, or full-tower. The terms are subjective and inconsistently defined by different manufacturers.
Full tower cases are typically or more in height and intended to stand on the floor. They can have anywhere from six to ten externally accessible drive bays. These cases were originally developed to house which would typically be tasked with serving data from expensive CD-ROM databases that held more data than the hard drives commonly available at the time. Hence, many full tower cases include locking doors and other physical security features to prevent theft of the discs. However, as computing technology moves from and to large capacity hard drives, USB flash drives, and network-based solutions, more recent full tower cases typically only have none, one, or two external bays for CD drives, with the internal bays moved elsewhere in the case to improve airflow. Today, full tower cases are commonly used by enthusiasts as showpiece display cases with custom water cooling, lighting, and tempered glass (replacing acrylic). They may also hold two computers (as is the case with the Corsair 1000D) and dual power supplies (Corsair 900D).
Mid-tower cases are smaller, about high with two to four external bays. They may also hold two computers.
A mini-tower case will typically have only one or two external bays.
The marketing term midi-tower sometimes refers to cases smaller than mid-tower but larger than mini-tower, typically with two to three external bays. Other times the term may be synonymous with mid-tower.
Alternatively, the case may have a single large U-shaped cover that saddles the chassis. This was ubiquitous in AT tower cases.
To prevent the buildup of performance-degrading dust within the case, many models feature dust filters in front of the air intake fans. While the exact method of accessing the front filters depends on the case model, it usually requires the removal of the entire front panel. Removal of the front panel itself may or may not require the removal of one or both of the side panels. If there is any doubt, consult the user's manual if possible.
Traditionally, most computer cases required computer case screws to hold components and panels in place (i.e. motherboard, PSU, drives, and expansion cards). From the early 2000s onwards there is a trend towards tool-less 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 and is also cheaper to manufacture.
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 colored internal lighting, custom paint, or Watercooling. Some hobbyists build custom cases from raw materials like aluminum, steel, styrofoam, acrylic, or wood.
Historically, cases used CCFL lighting and eventually single color LEDs as strips or in fans to illuminate their interior; modern cases use RGB LED lighting instead, often incorporated into case fans. To improve airflow while allowing RGB fans to be visible, many cases as of 2020 use metal meshes, without any external bays. Many include a PSU shroud and vertical gpu mounts. Some used to include holes to support external water cooling radiators. Cases with side windows may have side fans (on the window) as well, although it is uncommon for cases with glass windows to have side fans.
In the past, many tower cases (including full tower cases) intended to house featured a Round-key lock door covering the external drive bays. This was a security feature intended to prevent the theft of the CD-ROM discs the drives would be holding. At the time, CD-ROM capacity was larger than the hard disks available, and many business-critical databases were distributed on this media. These databases were often very expensive or held proprietary data, and hence would be likely targets for casual theft.
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