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.