Hardware

A personal computer is made up of multiple physical components of computer hardware, upon which can be installed an operating system and a multitude of software to perform the operator's desired functions.
Though a PC comes in many different form factors, a typical personal computer consists of a case or chassis in a tower shape (desktop) and the following parts:

[edit] Motherboard

The motherboard is the "body"[citation needed] of the computer. Components directly attached to the motherboard include:

* The central processing unit (CPU) performs most of the calculations which enable a computer to function, and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan.
* The chipset mediates communication between the CPU and the other components of the system, including main memory.
* RAM Stores all running processes (applications) and the current running OS. RAM Stands for Random Access Memory
* The BIOS includes boot firmware and power management. The Basic Input Output System tasks are handled by operating system drivers.
* Internal Buses connect the CPU to various internal components and to expansion cards for graphics and sound.
o Current
+ The northbridge memory controller, for RAM and PCI Express
# PCI Express, for graphics cards
+ PCI, for other expansion cards
+ SATA, for disk drives
o Obsolete
+ ATA (superseded by SATA)
+ AGP (superseded by PCI Express)
+ VLB VESA Local Bus (superseded by AGP)
+ ISA (expansion card slot format obsolete in PCs, but still used in industrial computers)
* External Bus Controllers support ports for external peripherals. These ports may be controlled directly by the southbridge I/O controller or based on expansion cards attached to the motherboard through the PCI bus.
o USB
o FireWire
o eSATA