Motherboard & System Unit System Unit The box in which the motherboard and other components of the computer is stored. On a desktop computer it’s typically a box that contains everything except the input/output peripherals (monitor, keyboard, mouse, printer, speakers, etc). On a notebook, it’s the box under the keyboard. On some desktop units, it’s built into the screen (iMac, HP 6000 pro, etc) System Unit (continued) The system unit (usually) contains: Motherboard Hard drives Optical Drives Power Supply Expansion cards Expansion ports Motherboard The motherboard (aka the parent board by pc individuals or the logic board by Apple) is a printed circuit board to which is attached the CPU, miscellaneous integrated circuits such as ROM and connectors for memory, storage, video, keyboard, mouse and other ports. Most motherboards today are integrated with sound, graphics, wired and wireless network Power Supply The power supply suppiles power to a computer. It converts AC power to DC and splits it off to various voltages needed by the components of the system. On a notebook computer, the battery supplies power to a converter which splits off the various voltages. The battery is charged by an external charger called a brick. Expansion (controller) cards Expansion cards can be plugged into slots on the motherboard (of desktop systems) to provide capabilities not provided by the motherboard. Since most modern motherboards have most capabilities built in these are no longer necessary for most systems. Typically they are used for high-end graphics, RAID, tv tuners. Ports In the context of hardware, ports refer to connectors between the computer and external devices. Among common ports are: Parallel ports – uncommon today, formerly used to connect printers Serial ports – also uncommon, formerly used for mouse PS/2 ports – used to connect a keyboard or mouse to a PC compatible computer. These are becoming less common Ports (continued) USB port (universal serial bus) – USB 1.1, 2.0, 3.0 Firewire port – aka IEEE 1394 LightPeak (Thunderbolt) Video ports – used to connect a monitor. There are a variety of different connections:VGA, DVI, Display port Ports (Continued) SCSI – (small computer systems interface) primarily used for connecting storage devices such as hard drives, tape drives, optical drives, usually to servers. These connections are usually internal. SATA – (Serial ATA) typically used to connect hard drives, optical drives internally. ESATA is an external SATA connector.