Typical PC hardware

A typical personal computer consists of a case or chassis in a tower shape (desktop) and the following parts:

Motherboard

• Motherboard - It is the "body" or mainframe of the computer, through which all other components interface.
• Central processing unit (CPU) - Performs most of the calculations which enable a computer to function, sometimes referred to as the "brain" of the computer.
• Computer fan - Used to lower the temperature of the computer; a fan is almost always attached to the CPU, and the computer case will generally have several fans to maintain a constant airflow. Liquid cooling can also be used to cool a computer, though it focuses more on individual parts rather than the overall temperature inside the chassis.
• Random Access Memory (RAM) -It is also known as the physical memory of the computer. Fast-access memory that is cleared when the computer is powered-down. RAM attaches directly to the motherboard, and is used to store programs that are currently running.
• Firmware is loaded from the Read only memory ROM run from the Basic Input-Output System (BIOS) or in newer systems Extensible Firmware Interface (EFI) compliant
• Internal Buses - Connections to various internal components.
• PCI (being phased out for graphic cards but still used for other uses)
• PCI-E
• ISA (obsolete in PCs, but still used in industrial computers)
• USB
• HyperTransport
• CSI (expected in 2008)
• AGP (being phased out)
• VLB (outdated)
• External Bus Controllers - used to connect to external peripherals, such as printers and input devices. These ports may also be based upon expansion cards, attached to the internal buses.

Power supply

A case control, and (usually) a cooling fan, and supplies power to run the rest of the computer, the most common types of power supplies are AT and BabyAT (old) but the standard for PCs actually are ATX and Micro ATX.

Storage controllers

Controllers for hard disk, CD-ROM and other drives like internal Zip and Jaz conventionally for a PC are IDE/ATA; the controllers sit directly on the motherboard (on-board) or on expansion cards, such as a Disk array controller. IDE is usually integrated, unlike SCSI Small Computer System Interface which can be found in some servers. The floppy drive interface is a legacy MFM interface which is now slowly disappearing. All these interfaces are gradually being phased out to be replaced by SATA and SAS.

Video display controller