The
most important component of any computer is the Motherboard. The
Motherboard is the largest board of the computer system. It is also
called System Board. The motherboard is located on the left side of PC’s
case on the bottom. It is usually green sheet of fiberglass with many
chips, resistors, the heat of the computer i.e. power supply and
contains many other organs of the computer system. It also contains the
memory i.e. ROM and RAM and many other supporting logic circuits to make
the complete computer work as a proper system. Instead of “motherboard”
IBM refers to its as “System Board” or “Planer Board” but sometimes
other manufacturer refers to it as “logic Board”. It accepts the CPU,
memory, various plug-in peripherals, connectors and supporting
circuitry. The motherboard defines the type of system by defining the
type of processors it accepts, by the chipset features and by its
architecture.
IBM decided that there should
be used two different types of technologies, which were being used to
make personal computer. They are:
Bus Based Computer.
Single Board computers.
Bus Based Computer
1. Address Bus
2. Data Bus
3. Control Bus
Address Bus:
Group of lines carrying the addressing information used to describe the
memory location to where the data is being transferred.
Bus Based Computer
Data Bus:
A set of lines used to carry the data.
Control Bus:
I is used for carrying a set of control signals that control the flow of data.
These all buses are provided on these boards. The main advantage of
this type of board is that, whenever any part fails, the board on which
that part is located can be removed and replaced with a working board,
very easily and so it makes the maintenance of the system very easy. In
these types of computers, different parts of a system such as main
processor, memory, display card etc. are put on separate cards and
connected to the main system bus through expansion slots.
Single Board Based Computers
The
other approach in the computer design is a single board based systems.
These types of boards contain all the chips and circuits to make a
proper system. These types of boards are easy to manufacture and design
and it is less expensive than bus based type of computers. The video
games computers and home computers and generally this type of system. In
these systems, we cannot connect any other additional device; all the
devices are available on motherboard itself.
Single Board Based Computers
These
bus-based computers have used the main board as the backbone of the
computer system. This bus board contains number of buses through which
the data can be sent from one place to another and it also contains the
number of slots onto which we can connect various different devices.
Mainly the expansion cards are connected onto the expansion slots. In
this type ob bus based computer there are three buses. These are:
There is no option or have in no scope of upgrading or adding any new
device introduced in the market to these systems. In these types of
systems if and of the components fails, the user will have to discard
the complete circuit board means that we cannot repair or maintenance
any to the component.
When the IBM first introduced the system in the market, they have decided that they will use the
single
board based computers. This board contains almost all the important
parts of a computer such as main processor, memory, support chips etc.
But all the same time it has provided the expansion slots (i.e. Bus
based system) on the main board to connect new additional device to the
system. Also, some common I/O devices such as display, serial/parallel
interface, storage devices etc. are connected to the basic system
through these expansion slots. So, this design gives the popularity to
the whole world and it makes the systems more reliable and at the same
times the slots on the motherboards provide facility for future upgrade
and maintenance of the system and it makes so easy as compared to single
board based systems.
As already mentioned on the
CASE page, the main major architecture these days is ATX. Make sure that
you buy the motherboard architecture that you case and power supply
supports, or that you buy the right case for your motherboard. AT and
ATX motherboards for example have different power connectors, different
sizes, different mount holes, etc, but most importantly, a different
back panel.
Alongside a variety of connectors, a modern domestic ATX motherboard normally features:
· One AGP (Accelerated Graphics Port) Slot.
· Five or six PCI (Peripheral Component Interconnect) Slots
· Maybe one or two older EISA (Enhanced Industrial Standard Architecture) Slots
· Two to four SIMM or DIMM (Memory Modules) sockets
· One CPU (Central Processing Unit) Socket or Slot
· One parallel Port (LPT1)
· Two Serial Port (COM & COM2)
· Two USB (Universal Serial Bus) connectors
· One Floppy Drive Port
· Two EIDE (Enhanced Integrated Drive Electronics) Sockets
· One PS/2 (Personal Integrated Drive Electronics) Sockets
· One PS/2 mouse connector
Depending on the make, some motherboards also feature:
· Onboard Sound
· One Joystick/Game Port
· Onboard Video
Motherboards
that are aimed at the server market might even feature more than one
CPU socket/slot, onboard SCSI and more memory sockets, network adapters,
etc.
Selecting a good motherboard is of almost
importance when deciding for a system. Be very selective and make sure
that the board of your choice supports the kind of system you want to
build. It has to accommodate the type and speed of your Processor, your
preferred system bus type, your preferred type and amount of memory and
any other features or onboard facilities you want. When buying your
motherboard, always make sure you go for a major brand, it really pays
off! Also make sure you get your motherboard manual, without which you
are stranded come the time of your next CPU upgrade. The manual tells
you about the features and the BIOS of the board and how to set the
jumpers, switches and BIOS settings.
In both the AT and ATX designs, the computer components included in the motherboard are:
· Chipset
· Microprocessor (CPU)
· RAM
· ROM
· Math Co-processor
· System Clock
· Keyboard connector
· Mouse connector
· DIP switches
· Jumpers
· Bus Architectures
· Expansion Slots
· Different types of Adapters
