The motherboard is the main component of a personal computer. It contains the major structures that make up the computer system. Its characterized by the form factor, type of processor socket used and by the input-output connectors it can handle.
POWER SUPPLY
It is in charge of converting standard energy into a form which a computer can use. It is also responsible for (…….) up every device in the computer. The characteristics of power supply describe the quality of its output, its ability to handle such situations such as disruptions or disturbances to its input power and variations in the loads of power supply drives.
CPU
It is the central processing chip of the computer and processes instructions from the operating system and the software running on the computer. It is characterized by the chip speed it has. The (…..) co-processor, cache memory and buses.
STORAGE DEVICES
A storage device is a hardware device designed to store data. There are two types :-primary storage and secondary storage devices.
Primary storage offers permanent storage and stores data independent of the power supply e.g. hard disk.
Secondary storage is a volatile memory and a fast accessing memory that is used for executing instructions. It stores temporary data so long as the power is on.
The major magnetic storage media are floppy disks, (…..) disks and tape.
MEMORY MODULES
Memory is mandatory to make the microprocessor and the PC to work. It also determines what programs you can run and how fast. There are two types of memory modules DIMMS (Dual in line memory modules) and SIMMS (Single inline memory module)
A DIMM is a series of ram chips mounted on a small printed circuit board. They have 168-pin connectors and support 64-bit data transfer.
A SIMM is a small circuit board designed to hold RAM chips and there are two types:- 30-pin SIMMS and 72-pin SIMMS.30-PIN SIMMS has 8-bit data transfer buses while 72-pin SIMMS have 32-bit data transfer buses.
DISPLAY DEVICES
Also termed as the Visual Display Unit, it can be described as an electronic device that transmits information from the computer on to a screen hence acting as an interface and connecting the viewer with the computer. It can be categorized into two types: The CRT (Cathode Ray Tube) and the LCD (Liquid Crystal Display) technology.
CRT
They employ the technology used commonly in the manufacture of television screens. These monitors are highly reliable, efficient and are capable of generating a resolution up to 2048*1536 pixels thereby providing clear picture quality.
LCD
It is one of the most advanced technologies available at present. There are two different types of LCD technology available. These include active matrix or TFT and a passive matrix technology. Among these TFT technology is much more secure, reliable and generates better picture quality on the other hand, passive matrix has a slow response time and is slowly becoming out dated.
ADAPTER CARDS
Adapter cards are devices that allow one system to connect and to work with another. Typical adapter card used with PCs include: - Video adapter, Modems, LAN cards and Sound cards.
VIDEO ADAPTER CARDS
Provides an interface between the system board and the display monitor. The most common type of video adapter card currently in use is the Video Graphic Array (VGA).It uses analog signals and (……) rather than digital signals.
MODEMS
Devices used to carry out data communications through telephone lines.
LAN CARDS
Used to connect the local system to a group of other computers so they can share data and resources.
SOUND CARS
Devices used to provide high-quality audio out-put to the computer system.
PORTS
The term port can either refer to physical or virtual connection points.
Physical network ports allow connecting cables to computer routes, modems and other peripheral devices which include:- the Ethernet ports, USB port and serial ports.
Virtual ports allow software applications to share hardware resources without interfering with each other.
CASES
The system unit case is typically a metal chassis and a removable cover that includes a plastic front panel for aesthic purposes. This box typically contains the basic parts of the computer system.PCs have been packaged in a number of different case designs. Each design offers characteristics that adapt the system for different environments. They include :- (……) methods for the printed circuit boards, ventilation (……), total drive capacity, foot print and portability.
(B)
SERIAL PORTS
Serial ports transmit data one bit at a time and are relatively slow compared to other ports. They are however fast enough for some external devices such as a mouse or an external modem. Because only one bit at a time is passed along a serial cable it can only travel a fair distance before errors start to occur. A serial cable should not be more than 50 feet in length.
PARRALLEL PORTS
They are less commonly referred to as the contronics interface or centronics connector. It is used to connect external devices that need to send or receive a lot of data over a short distance. The parallel port found on the back of IBM compatible computer is a 25-pin (DB-25) computer used to connect printers. The DB-25 connector has an 8-bit data bus supported by a maximum cable length of 15 feet.
USB PORTS
It has virtually replaced serial and parallel ports. They are faster and can be used to connect several devices to the system unit. It is unique in that it is completely hot swappable. It also allows you to daisy-chain up to 17.2 devices.
FIRE WIRE
Also known as IEEE-1394 it provides connections to specialized fire wire devices such as cam coders. It has a bandwidth of 400-800 mbps and can handle up to 63 units on the same bus, it is not hot swappable.
DB
It is the most common type of connector. It is of a 'D' shape and is sometimes called a D-shell connector. A-D B-9 female connector would be a 'D' shaped connector with 9 holes. This would receive a card with a DB-9 male connector with 9 pins.
RJ
The RT connector is used for communication devices. These are two types:-RJ-11 and RJ 45 connectors. The RJ-11 connects 4 to 6 wires and is used on modems and telephones. It is also smaller than the RJ-45 which is used for Ethernet connections to NIC.
DIN The DIN connector is a small round connector usually with a keypad for proper orientation. It is fairly popular because of its small size and solid connection. The PS\2 or DIN-6 connector has become the standard for both the keypad and the mouse on newer PCs.
MINI-DIN
It is a part you could find on the back of an older computer and is commonly referred to as DIN-9.A BOS mouse or hand-held scanner may use this type of port.
CENTONICS
The centronics connector is a parallel interface connector. It has 8 parallel data lines which allow data to travel 8-bits at a time. The centronics connector is designed as centronics-x with the 'X' representing the number of data or connectors it has.
