Editing Computer case (section)

==Layout==
Computer cases usually include sheet metal enclosures for a [[Power supply unit (computer)|power supply unit]] and [[drive bays]], as well as a rear panel that can accommodate [[peripheral]] connectors protruding from the motherboard and [[expansion slot]]s. Most cases also have a power button or switch, a [[reset button]], and [[LED]]s to indicate power, hard drive activity, and network activity in some models. 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 (normally) include the wires needed to connect these ports, switches, and indicators to the motherboard.<ref>{{cite web |last1=Ryley |first1=Nick |title=What Are Front Panel Connectors? |url=https://thepcgeekz.com/what-are-front-panel-connectors/ |website=ThePCGeekz}}</ref>

===Major component locations===
* The [[motherboard]] is usually screwed to the case along its largest face, which could be the bottom or the side of the case depending on its form factor and orientation.
* Form factors such as [[ATX]] provide a back panel with cut-out holes to expose [[I/O port]]s provided by [[integrated peripheral]]s, as well as [[expansion slot]]s which may optionally expose additional ports provided by [[expansion card]]s. Many larger ATX cases can also be used with motherboards of other form factors.
* The [[Power supply unit (computer)|power supply unit]] mounting point differs from case to case, but the most commonly used locations (both at the rear of the case) and their advantages/disadvantages are:
**The top of the case, usually allowing the PSU's built-in fan to act as an auxiliary exhaust fan but causes the PSU to be fed air heated by the internal components of the case, thus causing PSU efficiency and lifespan degradation.
**The bottom of the case, with an (often filtered) vent in the bottom of the case allowing the PSU to draw cool air from the outside.
*Regardless of the mounting position, the PSU will usually be attached to the case with four [[screw]]s to support its weight.
* Most cases include [[drive bay]]s on the front of the case; a typical ATX case includes [[5.25"]], [[3.5"]] and 2.5" bays. In modern computers, the 5.25" bays are used for [[optical drive]]s, the 3.5" bays are used for [[hard drive]]s and [[card reader]]s, and the 2.5" bays are used for [[solid-state drives]].
* Buttons and LEDs are typically located on the front of the case; some cases include additional I/O ports, temperature, and processor speed monitors in the same area.
* Vents are often found on the front, back, top, left side panel, and sometimes on the right-side panel of the case. Regardless of their placement, their purpose is either to let cool air into the case or to let hot air out. Larger vents usually allow [[computer fan|cooling fans]] to be mounted via surrounding threaded screw holes. Newer cases include mountings for larger 120 mm or 140 mm cooling fans for quieter operation than the 80 mm fans formerly common.
* An I/O template, or I/O plate, fits around the motherboard's back panel of external ports. Sometimes provided by the case manufacturer, it is often replaced by the one that comes with the motherboard.

===Internal access===
Accessing the interior components of a modern [[ATX]] tower case is done by removing the side panels. Looking front-to-back, accessing the motherboard, PSU, drive bays, and most case fan installation points are done by removing the left side panel.
Removing the right-side panel is done less often to access the space behind the motherboard mounting plate. This space is devoted to cable management, as cables routed in front of the motherboard may disrupt the flow of air within the case causing increased temperatures.<ref>{{Citation|last=Linus Tech Tips|title=Cable Management – Does it impact cooling performance? At all?...|date=2016-02-08|url=https://www.youtube.com/watch?v=YDCMMf-_ASE |archive-url=https://ghostarchive.org/varchive/youtube/20211222/YDCMMf-_ASE |archive-date=2021-12-22 |url-status=live|access-date=2018-08-11}}{{cbignore}}</ref> [[BTX (form factor)|BTX]], an uncontemporary standard, has the main side panel on the right side as opposed to the left. Some upside-down designed ATX cases are also accessed by removing the right-side panel door.

Alternatively, the case may have a single large U-shaped cover that saddles the chassis. This was ubiquitous in [[AT form factor|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.