Basic Computer Maintenance EW

Basic structure of a Computer

Computer Maintenance


Basic structure of a Computer

Chapter 1: Overview of a
Computer
• Show a typical PC system


Basic structure of a Computer
•

Proper Terminology
• Case
• Power supply
• Motherboard (main board)
• Expansion slots
• CPU (Central Processing Unit)
• RAM (Random Access Memory)
• HDD (Hard disk)
• BIOS (Basic Input Output System)
• Optical Drive
• Floppy Disk
• Ports
• Modem
• Monitor (Display)
• Sound card (Multimedia device)
• Video card (Graphics adapter)

• Network card (Network adapter)


Detail of PC components


Detail of PC components

Chapter 2: Cases and power supply
•Case: The cabinet that holds main components of a PC
•Power supply: use 110V or 220VAC and it is converted to 5V
and 12VDC to provide power for components of the PC.


Detail of PC components
AC power connectors:
• AC power input is connected through a standard CEE threepronged power cord.
• AC power connector is used with almost PCs, including Macs,
some laptops, power supplies, and many other devices.


Detail of PC components
DC Power Output Connectors
DC connector is an electrical connector for
supplying directly current DC power


Detail of PC components

Chapter 3: Motherboard and its Components

What is motherboard ?
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Motherboard is a part of the computer. It is called main
board.
It is the circuit board, holds many crucial system of the
system. It is used to connect to other components.
It contains the processor socket (s), memory slots,
expansion card slots, ports for mouse, keyboard,
printer, …, and electronic parts …


Detail of PC components
Motherboard
Components
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CPU slot/socket
Memory slots

BIOS chip
Chipset
AGP slot
Expansion slots (ISA and PCI)
Power connectors
Battery
Disk drive connectors
Ports and Built-In (Onboard) Components


Detail of PC components
2. Chipset
• Every motherboard has a number of integrated circuits (chips or
ICs) permanently installed on different parts of the board. Each
chip has a separate function.
• Based on Intel Pentium-class microprocessors, the term chipset
often refers to a specific pair of chips on the motherboard: the
north bridge and the south bridge


Detail of PC components
3.
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AGP slot (Accelerated Graphics Port)
This is the slot for video adapter

Year created 1997
Created by Intel
Since 2004, PCI-E (Peripheral Component Interconnect
Express) has been gradually replacing AGP.
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Detail of PC components
4. Expansion slots (ISA and PCI)
• Expansion devices in card form, such as modems and network
adapters, go into these slots.
• PCI (Peripheral Component Interconnect)
- It was a computer bus standard to transmit data between the
peripheral devices to the main board by south bridge chipset.
- Year created: July 1993
- Created by Intel


Detail of PC components

• ISA (Industry Standard Architecture)
- It was a computer bus standard for IBM compatible computers.
- Year created 1981
- Created by IBM


Detail of PC components
5. Power connectors
• Every motherboard has power connectors. It was divided into two
kinds ATX and AT power

Detail of PC components
•

There are two basic differences between AT and ATX power
supplies:
- The connectors provide ATX power to the motherboard is
the soft switch.
- On older AT power supplies, the Power-on switch wire
from the front of the computer is connected directly to the
power supply.
- Wiring diagrams of AT and ATX power follow the link
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Detail of PC components
6. Disk drive connectors
• Every motherboard has two IDE connectors for up to four IDE
devices.
• It usually uses one or two hard drives and one or two optical (CD or
DVD) drives

• IDE connectors use old ATA (AT Attachment) standard with low
bandwidth (16Mb/s and 133Mb/s).


Detail of PC components
• Nowaday, technology has used SATA standard (Serial ATA) with
high bandwith (1.5, 3.0, 6.0 Gbit/s)

Detail of PC components
7. Ports and Built-In (Onboard) Components
Motherboards have some or all of the following ports:
- Serial:
serial port is a serial communication physical interface through
which
information transfers in or out one bit at a time
- Parallel:
In computing, a parallel port is a parallel communication
physical
interface. It is also known as a printer port.
- PS/2 mouse:
It is a 6-pin used for connecting some keyboards and mouse to
a PC. Its name comes from the IBM Personal System/2 series of
personal computers
- USB (Universal Serial Bus)
is a specification to establish communication between devices
and a host controller (usually a personal computer)


Detail of PC components
- Ports and Built-In (Onboard) Components


Detail of PC components

Chapter 4: Memory
(RAM)
1. Memory Overview

• Computer memory is electronic circuitry that holds binary data.
• The ‘On’ position represents the binary 1, and the ‘Off’ position
represents the binary 0. Each 0 and 1 is called a bit.
• The switches are divided into groups of eight bits, called bytes.
• A byte is an 8-bit number that can equal any decimal number
between 0 (all 0s) and 255 (all 1s), and is the basis of all
computer data.
• For more information on binary number, we go to
/>• Main memory in computers comes in modules, often called
sticks, which can contain billions of switches. Memory sticks are
measured in megabytes (MB), and soon, gigabytes (GB).
• The acronym RAM stands for random access memory.


Detail of PC components
2. Memory types
• There are many types of memory used today. They differ mainly
in available speeds and cost.
• Motherboards are limited to one type of memory.
• Common memory types include
- SDRAM (Synchronous dynamic random access memory)

Note: - DIMM or dual in-line memory module,
- DIMMs began to replace SIMMs (single in-line memory
modules) as the predominant type of memory module.
- Two types of DIMMs: a 168-pin SDRAM module (top) and a
184-pin DDR SDRAM module
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Detail of PC components

- DDR SDRAM, sometimes called DDR1

- Comparison of DDR, DDR2 and DDR3 for Desktop PCs


Detail of PC components


Detail of PC components
3. Memory speed
• Motherboards can accept memory modules in certain ranges
of speed, for example 100, 133 or 266MHz …
• The faster the memory, the faster the performance of the
computer.
• As in memory type, all memory installed in a single computer
should be the same speed (recommended)

4. Error detection and correction
• Memory has two types:
- ECC or parity (Error Correction Code)
- non-ECC or non-parity
• RAM with ECC or Error Correction Code can detect and correct
error.


• Error detection is the detection of errors caused by noise or other
Impairments during transmission from the
transmitter to the receiver.
• Error correction is the detection of errors and reconstruction of
the

original, error-free data.
• Parity memory can compensate for single-bit errors.
• This parameter is specified by the motherboard manufacturer,
but is
changeable in some BIOSs