Basics of Computer Hardware
HISTORY OF COMPUTERS
First computer made by human being is abacus .It is a frame containing rods in which small ball moves from right to left and left to right.
In 1812 CHARLS BAGGE who was professor of mathematics in
In 1880 HERMAN introduced punch card machine.
In 1896 HERMAN established T.M Machine Company then this company merged in IBM.
1910 JAMES powers introduced punch card processing machine.
In 1937 HOWARED AIKEN (U.S.A.) made a machine that was able to perform more then one calculation simultaneously.
In 1944 MARKE I & MARKE II computers were introduced at the same time in 1947 ECKERT and MICHLAY (scientists) designed a machine named ENIVACE (pronounced as ANYWESS) but failed.
ANYWESS is then modified and named as EDIVAC. First in this computer machine language or binary or digital language was used. This language is still used in our computers in very advance form.
In April 1951 IBM (computer manufacturing company) introduced ibm-701 and IBM-705 computers these computers ruled for seven years in the computers world.
GENERATIONS OF COMPUTER
FROM 1951 TO 1959 i) THE FIRST GENERATION OF COMPUTERS
FROM 1959 TO 1965 ii) THE SECOND GENERATION OF COMPUTERS
FROM 1965 TO 1970 iii) THE THIRD GENERATION OF COMPUTERS
FROM 1970 TO 1984 iv) THE FOURTH GENERATION OF COMPUTERS
FROM 1984 UP TO v) THE FIFTH GENERATION OF COMPUTERS DETAIL:
INTEL MICROPROCESSORS DETAIL (FIFTHE GENERATION)
8046 LESS THEN 1MHZ
8080 LESS THEN 1MHZ
8086 1MHZ 2MHZ
XT 2MHZ 10MHZ
286 10MHZ 12MHZ
386 12MHZ 33MHZ
486 33MHZ 100MHZ
586 100MHZ 133MHZ
PENTIUM SERIES
PENTIUM PRO, PENTIUM 1 75MHZ 233MHZ
PENTIUM II 233MHZ 450MHZ
PENTIUM III 450MHZ 1400MHZ
PENTIUM IV 1500MHZ 3,200MHZ
IN FUTURE ANATIUM
OR PENTIUM SUPREME
EXPECTED
ELECTRICAL AND ELECTRONICS TECHNOLOGY
ELECTRICAL CURRENT:
The flow of electrons is called as current electricity.
AC CURRENT:
It is such a current (flow of free electrons), which changes its direction and magnitude with time.
Graphically:
One cycle/sec
Frequency = 1 Hertz
DC CURRENT:
It is a type of current, which flows only in one direction, and its frequency is always zero.
Graphically:
Dc current frequency = (0)
In
ELECTRICAL AND ELECTRONICS COMPONENTS
RESISTANCE:
It is the property of a material filter DC current.
TRANSISTOR:
It is three layer P & N type semiconductor device used for amplification, switching, storing data in the electronics of the computer.
TRANSFORMER:
It consists of two coils primary coil and secondary coil. It is used to step up the input voltage also used to step down the input voltage.
WORKING PRINCIPLE OF TRANSFORMER:
Transformer works on magnetic induction, principle. The input voltage produces magnetic field in the primary coil, this magnetic field produce voltage in the secondary coil. The turns of the coil are responsible for the out put voltage.
PROJECT:
Manufacturing of 12 volt DC Power Supply
Required Components, Transformer 12 volt 1AMP, Rectifier Diodes 4 Nos., 18 volt 4600 UF Capacitor 1 No., 7812 Regulator, 1 No.
WHAT IS COMPUTER?
Computer is an electronic device capable of performing calculations of computations and making logical decisions at thousand times faster even million times faster then the human being.
COMPUTER PROGRAM:
Computer process the data under the control of a set of instructions called computer program.
COMPUTER HARDWARE & SOFTWARE:
HARDWARE:
The electronic magnetic and mechanical components of the computer system is called as computer Hardware.
Infect these are the physical Components which can be touched or handle or seen physically.
These devices include input devices like Keyboard, Mouse, Digital Camera, Scanner, Microphone, Joystick, Light Pen, Note Pade, Track Ball etc. System Parts, Motherboard, Microprocessor, RAM, Floppy Drive, Tape Drive,
SOFTWARE:
The program made of series of instructions that tells the computer what to do and how to do.
COMPUTER PARTS / COMPONENTS
INPUT DEVICES / PARTS:
Keyboard
Mouse
Joystick
Microphone
Note Pad
Scanner
Digital Camera
Track ball
Light Pen
SYSTEM DEVICES / PARTS
Mother Board
VGA Card
Sound Card
Microprocessor
RAM
Floppy Drive
Tape Drive
Zip Drive
Smart
OUT PUT DEVICES / PARTS
Monitor
Speakers
Laser Printer
Dot Matrix Printer
Video projector
Image Setter
Modem
COMPUTER BASICS:
Computer is an electronic device for storing and processing data at very high speed according to the instructions given to it in a variable program.
A digital computer can operate at the speed of several million instructions per second. It is made up of different parts connected together. There are three basic functional units in a computer.
The computer system consists of three basic units.
1. Input Devices.
2. System Unit
3. Out put Devices.
INPUT DEVICES:
These are those devices through which we send the input signals to the computer system. This device includes devices like, Keyboard, Mouse, Microphone, etc.
2. SYSTEM UNIT:
This is the central part of the computer system we connect input devices and out put devices to this unit. It receives the input Data/Signals from the input devices and processes that data and prepares information and send that information (Result) to the concerned out put devices. These devices/parts includes the below items:
Necessary System Parts: Motherboard + Sound + VGA Card + Microprocessor + RAM + Hard Disk + Floppy Disk Drive + CD Rom Drive + Power Supply.
3. OUT PUT DEVICES:
These are connected to the system unit. These devices receive the information/Results and convey it to the users.
Necessary Out Put Devices: Monitor + Speaker + Printer + Modem etc.
POWER SUPPLY
Every thing need power to operate Example a car need fuel to start the engine so that to run the car. An electrical fan needs electricity to produce Air Blow. Tube light also needs electricity to produce light.
In the same way all computer parts need electrical Power to operate.
The Section that supplies DC Electrical Power to the computer parts/components is called a power supply. It is a box fixed in the upper back side of the computer case. (Tower Casing).
The Power Supply receives AC Electrical current through the Power cable and converts it in to different DC voltages. I.e., +12, -12, +5, -5. Which all computer parts need to operate OR Which is the requirement of all computer parts.
TYPES OF POWER SUPPLY
There are two types of Power Supplies:
1. AT Power Supply.
2. ATX Power Supply.
1. AT POWER SUPPLY:
It is such type of Power Supply which ON/OFF function is manually controlled, i.e., at the input a two-way switch control the input electricity of the power supply. When the switch is at OFF position the Power Supply out put is zero and when the switch is ON the Power Supply gives out put, i.e., DC Voltages.
In the fig “A” the switch of the AT Power Supply is at OFF position so at the out put the voltages are zero (0) and in the figure “B” the switch is turned to ON position the EC voltages are available at the out put wires of the AT power supply.
In AT Power Supply when we start preparation to shut down the computer we follow the below steps. Start Menu Shut Down OK. The computer start to go to Shut Down finally message appears on the screen i.e., It is now safe to turn OFF your computer. After that we turn the switch of the power supply and then the Computer completely Shut Down.
ATX POWER SUPPLY:
It is such a power supply which ON/OFF function is Electronically / Automatically Controlled. Using ATX Power Supply when we shut down our computer in the window the Computer Shut downs completely. No need to switch OFF any knob. Their Power Supply directly receives usually input AC current 220 volts.
When the green wire is connected to the black wire the Power Supply starts giving DC out put. And when it is disconnected it stops and out put becomes zero.
CONNECTORS OF THE AT POWER SUPPLY
There are three types of connectors in the AT Power Supply.
1. Berg Connector.
This connector is used to Supply DC Power to the floppy Disk Drive the floppy Drive may be 3.5” or 51/4”. Some 51/2” Floppy Disk use the Molex connector.
2. Molex Connector.
This is four Pin D type female connector used to supply DC Power to the
3. P8 – P9 Connector.
These two connectors Supplies DC Power to the Mother board and all attached Components to the Motherboard.
Important: When we fix P-8 and P9 connector in to Mother board the black wires of each connector should be practical adjacent to each other.
CONNECTORS OF THE ATX POWER SUPPLY
1. Berg 2. Molex. Berg connectors supplied DC Power to Floppy disk Drive & Molex connector’s supplies DC power to the Hard Disk,
P8 – P9 in the AT power supply is replaced by a single connector in the Atx power supply called ATX Connector in the ATX Power Supply called ATX connector. It is 20-pin connector fixed in only one way.
POWER SUPPLIED SWITCHING
PRACTICAL
MOTHER BOARD
The spine of the computer is the Mother board otherwise known as system board. This is the olive green or Brown, Blue (depending upon the manufacturer fibre glass sheet that is fixed in to the bottom of the computer casing. The colour doesn’t have any effect on the performance of the mother board. All other computer components are attached to this sheet.
On the system board you will find CPU, under lying circuitry, expention slots, video components. Audio components, RAM Slots and a variety of other chip. When you see a motherboard you will notice thin lines, which are printed on the mother board, they are called printed circuits. They are made of copper and they are used to connect different components of the mother board.
TWO MAJOR TYPES OF MOTHER BOARD:
1. Built in Mother board / Integrated Mother board.
2. Plain Mother board / Non Integrated mother board.
1. BILT IN MOTER BOARD:
The name given to these system board is because most of the circuitry that would be installed as an expention card is integrated into mother board circuitry. Although they are cheaper to produce, they are more expensive to repair. When one components breaks the whole mother board must be replaced. Another choice is that to put another card of the component broken up and disable the useless component in the mother board.
2. PLAIN BOARD / NON INTEGRATED MOTHER BOARD:
The have each major assembly installed in the computer as an expention card. The major assemblies include items like video card disk controllers (1/0 card) Audio / Sound Card, Modem card, TV Tuner Card (Optional) and accessories. These motherboards are easily identified by the presence of such expention cards.
MOTHER BOARD SLOTS:
PGA
Stands for pin grid array
Used for processors.
Flat Shaped.
Processor is laid flat on its surface.
SLOT 1
It is used for processors.
But instead being flat the processor is fixed in vertical position.
Some mother boards have bother of these slots.
ISA SLOTS
ISA Stands for industrial standard architecture.
This is the old model of slots and is not used in the new coming mother boards.
These are big and usually black.
The reason for these slots being similar is that the number of companies is very large and they have settled a standard to interchange components the components that fit in these slots are compatibles.
EISA SLOTS
EISA stands for Extended Industrial Standard Architecture.
As the name states it is an extended form of ISA slots. They are smaller in size but have the same functions as ISA Slots.
PCI SLOTS
PCI stands for Peripheral component inter connect.
This is the latest form of slots and now a days only these slots are used.
They are small and usually cream coloured.
These are all similar in pin terms and do not very with different companies.
You can take its new industrial slots.
In the period when these slots were new and many components in the market were of ISA origination the companies produced mother boards with both ISA & PCI slots so that the market components do not get wasted but now mother board comes with PCI slots only.
BIOS
INTRODUCTION:
The term Bios stands for Basic Input and out put system.
In Layman terms it is also known as setup option.
The Bios chip is recognized by its small black shape and American Megatrends / AMI / Phonix Bios is usually written on it.
It is battery operated so that the data does not get washed away from it.
It is basically ROM (Read only Memory).
We can do alteration / modification (Change values) and not change the software in the Bios.
The battery is visible on the mother board.
TROUBLE SHOOTING:
Nowadays some viruses have been make which destroy the Bios software e.g., CIH virus is activated every year from 25th to 27th April. It destroys the partitions / Data and bios also. When the Bios of the mother board destroyed some people do the job to recover the bios software.
COMPONENTS OF MOTHER BOARD:
1. VGA CARD 2. Sound Card / Audio Card
3. Modem Card 4. Lan / NIC Card.
5. USB Card 6. Scuzzy Card
7. Special Purpose Cards etc.
MAJOR COMPONENTS / CARDS DETAIL
VGA CARD & SOUND CARD
VGA CARD:
VGA stands for video Graphic Adaptor. VGA Card is responsible to show the Graphics on the CRT (Cathode Rays Tube). It may be fixed in the form of single IC (Integrated Circuit) or in the form of a Card / Module in the mother board.
The video information coming from the source through the BUS the Video card receives that information and stores it and converts it into such a signal which monitor understands and that information is displayed on the screen in the form of light.
WORKING OF VGA CARD:
The VGA Card receives Digital image data from the computer System / Source (Hard Disk, CD ROM, etc.) and is stored in the VRAM. (Video RAM) Then the VGA chip scan the digital image and send it to the DAC Digital to Analog converter. Then the digital to Analog converter convert it to the Analog signal and send it out through the DB15 connector to the monitor. The monitor displays the information in the form of small light pixels. (Dots)
SOUND CARD:
It is such a type of module which enables computer system to produce sound and record sound through speaker / microphone. It may be fix in the form of IC / Card Module in the motherboard. The sound card receives the digital sound / codes and convert it to the Analog signal and send it out to the speaker through a stereo speaker jack. The sound card also converts our voice / sound waves (Through Microphone) in to digital form, which can be stored, send to somewhere else etc.
WORKING OF SOUND CARD:
The sound card receives the digital Audio signals from the source. The main chip of the sound do the job to convert digital audio signals to analog signals at the out put the signal is send to the amplifier. The amplifier energizes the weak out put of the sound card and drive the speaker producing loud sound waves.
On the other hand the microphone receives the sound wave and convert it to the Analog Electrical signal. This Analog signal is received by the sound card and the DAC the digital to Analog converter component convert it to the digital signal. This digital sound can be stored or process further.
So sound card convert Analog signals to Digital signals, and Digital signals to Analog signals.
ADC Analog to digital converter
DAC Digital to Analog converter
PROCESSOR OR MICROPROCESSOR OR C.P.U.
CPU stands for Central Processing Unit. It is the administrative section of the computer. It is also called the Electronic Brain of the computer. The roll of the Microprocessor is to control and direct all the activities of the computer.
It receives data from the input devices, process it and prepares information for the out put devices. Another important measurement of CPU performance is clock speed which is rated in Megahertz “MHz” one megahertz is equal to one million cycle per second.
C.P.U is the collection of three basic units.
1. MEMORY UNIT.
2. ARITHMATIC &N LOGIC UNIT.
3. CONTROL UNIT.
1. MEMORY UNIT:
This is also called main memory or primary memory. It retains the information which has been entered though the input devices so that the information may be made available when it is needed.
2. ARITHMATIC & LOGIC UNIT:
This is the calculation section of the computer. All arithmetic operations such as addition, subtractions multiplication and division as well and some logical operations are performed in this section. The logical operation make it possible for the computer to make decision at the result of comparisons of one item with another. ALU perform computation at tremendous speed as ordered by the control unit.
3. CONTROL UNIT:
It is the nerve center of the computer it co-ordinates and controls the computer system just as the brain directs the body. It operates the ALU as well as memory. It schedules the input out put operations. It is able to accept data from the input devices send it to the memory from the memory the data values are then transferred to the ALU and finally the result are send to the memory or out put unit.
HARD DRIVE:
Hard drive, Hard Disk or Hard disk drive is a primary device that the computer uses to store, access, manage information. Hard disk is the combination of Electronics and Mechanical. The electronic section includes the integrated circuits, and other circuitry. And interfacing connector which may be, 40 pin, 50 pins, or more or less depending upon the type of hard disk the circuit also have a male Molex connector through which harddisk receives DC power to work properly.
Usually Harddisk Card / electronic circuit or controller contains the connector through which Data can be send and receive by the Hard disk and a Male Molex connector through which hard disk receives DC power i.e., 12, -12, +5, -5. The controller also contain the master and slave jumpers.
The data cable contain three connectors. These three connector are same is size and shpae. One connector of one end is often fixed in the Mother board and is called system connector. Middle one is called slave connector and the opposite to the system connector is called master connector.
In the hard disk controllers we have master and slave jumper settings. If we are going to fix the master connector of the data cable then we will set of jumper on master in the Hard Disk controller. If we are intended to fix the hard disk one slave connector of the data cable the hard disk controller jumper should be set on slave location.
So master and slave jumpers in the hard disk controller is used for the above explained purpose.
Excluding hard disk controller the remaining part of the hard disk Drive is called Media.
Hard disk media consists of platters which rotates with the help of spindle motors with different RPMs i.e., Revolution per minute. Mostly board hard disk platters spins 4500, 5400, RPMs. Some latest hard disk platters spins 7200 RPMs and most recently newer hard drives platter spins 10000 RPMs.
Usually on the surface of the platters the data is megnetically stored. The read and write heads stores the data on the surface of the hard disk platters. Read and write head are also responsible for reading the stored data on the platters. The assembly of the read write head are responsible for the motion of heads over the platters. A connector is used to connect the hard disk controller with media. Through this connector the whole media receives power, and also data in and data out function is performed between the controller and media.
HOW DATA STORED/WRITE/READ ON HARD DISK PLATTERS:
Read and write heads are responsible for writing and reading the data on the megnetic surface of the disk platter.
The data which is to be stored in the hard disk drive platter is send in to the hard disk through the data cable the controllers receives that data and read write head write or store that data on the surface of the disk platter. The data is once stored in the hard drive. That is if required the read write head reads that data and send it out to the controller. This data is ready to travel through the data cable for further processing.
HARD DISK PARTITIONING:
Boot the system from bootable CD Rom.
Steps:
Switch on 1. Boot from Hard disk
2. boot from CD Rom
Select 2nd option and press enter button.
1. Start computer without CD Rom support.
2. Start computer with CD Rom Support.
3. Start WIN 98 setup from CD Rom.
Select the 2nd option and press enter button.
A:\>
The system has completed booting from CD Rom.
Here we will type Fdisk.
A:\> fdisk And press enter button two times
Reach fdisk main menu.
Fdisk
1. Create dos partitions.
2. Set active partitions.
3. Delete partitions.
4. Display partition information.
Enter Choice [ 1 ] selectr the choice through Keyboard, and press enter button.
CREATE DOS PARTITIONS:
1. Create primary dos Partition
2. Create Extended Dos partition.
3. Create Logical Dos drives in Extended Dos partition.
Enter Choice [ 1 ]
Verifying drive integrity (Goes from) 0% 100%.
Here a massege appears i.e., would you like to use the maximum available size of your hard disk as a primary Dost partition YES/NO [ N ] We will select N because, we are going to make partitions verifiying drive integrrity (goes from) 0% ti 100% a message apears Enter size in MB % to create primary Dos partition. [ 38000.00 ] Total size
Put the value for primary dos and press enter [ 8000 ]
Partition Status Type. Vol Lab M bytes System Usage
C: 1 Primary Dos 8000 Unknown 15%
The above message will appears on the screen now primary Dos partition is came in to being. And we will go back to fdisk main menu by pressing Esc Key once.
Now we are in the Fdisk main menu.
FDISK OPTION:
1. Creat Dos partitions:
2. Set active partitions.
3. Delete partitions.
4. Display partition information.
Enter Choice [ 1 ]
1. Create primary dos partition
2. Create extended Dos partition
3. Create logical dos Drive/partition in Extended Dos partition.
Enter Choice [ 2 ]
Here we will select the second choice because we have already completed primary Dos Partion.
Verifying Drive Integrity (goes from) 0% to 100%. An message appears.
Enter size in MB % to create extended Dos partition. [ 3000 ]
Note: Here we will just Hit the Enter so a screen appears. Containing the following informations.
Partition Status Type Vol Lable Mbytes System usage
C: 1 A Primary Dos 8000 FAT32 15%
2 Extended Dos 30000 FAT32 85%
Now we will press once Esc Key.
Verifying drive integrity (goes from) 0% 100% and message appears.
Enter Size in MB % to create Logical Dos Drive in Extended Dos partition. [30000]
Put the value according to your requirement [20000]
A screen appears.
Drive Val Lab Mbytes System Usage
D: 20000 FAT32 75%
Here drive integrity goes from 0% to 100% and again message appears.
Enter Size in Mb % to create logical Dos drive in Extended Dos partition. [10000]
At last just hit the Enter
Now screen will contain the below information.
Drive Vol Lable Mbytes System Usage
D: 20000 FAT32 75%
E: 10000 FAT32 25%
Now press Esc Key three times and Restart Computer.
CD’S
CD Rom Stands for compact disk read only memory this is the latest form of secondary storage device. It can store up to 650 MB (Mega Bytes) of data. It is used for long term storage of data. As the name states CD’s are normally read only nothing can be written on market re writable CD’s are commonly available. On the writable CD’s the writing task can be performed only once and the data once stored can not be deleted but in rewritable CD’s like floppy disks the data can gbe stored and deleted.
CD’s are popular mainly because it makes a great software distribution medium programs are getting larger and larger requiring more and more and more disks to install them, so instead of installing program using 100 floppy disks, you can use a single CD.
Now a days many types of CD’s have arrivedin the market. And each one has the capability to store more and more amount of data. But the thing, which is very intrusting is that, compaired to other CD players which are designed to play only one type of CD.
The
CD DRIVE BASIC WORKING PRINCIPLE:
The
The back pannel of the
FLOPPY DISK DRIVES:
A secondary storage device which is used to store data on the megnetic tape called floppy disks. Floppy Drives are of different sizes.
In Carlear Floppy drives size was 5.25” inches the floppy disk used in these were ranges from 360K and 1.2 Mega byte i.e., the diskets of these floppy drives can store 360 Kbyte and 1.2 M Byte of data. Another type of Floppy Disks were introduced the size of these floppy drive was 3.5” inches, although the size is reduced but data storage capacity were not improved satisfactorily. The storage capacity of these drives are 1.44MB, 2.88 MB respectively. These floppy drives are still in use.
In coming floppy Drives will be replaced by a sort of drives called smart Media which is progress. Thjese will be capable to store 2 MB, 4 MB, 8 MB,
MEMORY:
As the CPU of a computer processes data, it stores information in the computer memory. The rule of thumb is that the more memory of a computer has the better will be the operations. There are Three major types of computer memory.
1. DRAM/RAM
2. SRAM
3.
1. DRAM:
DRAM stands for Dynamic Random Access Memory. When you expand memory on a computer you are adding DRAM Chips. DRAM require a constant refresh signals or update signals to retain information. It is also called Read Write memory. Information can be read from it or written to it. It is temporary memory any thing stored in the RAM is lost when computer is switched off or if Power failure occu. Some time it is called as valatile memory.
2. ROM:
Stands for Read only Memory. It is called read only because once informatio has been written to ROM, it can not be changed. ROM is normally used for BIOS Software. ROM enables computer to pull it self by its boot straps.
BIOS
BIOS stands for Basic input and out put System. Basically it is a software stored on the IC. Which is located on every computer Mother board near allmost battery.
BIOS controls the basic functions of every computer system. The basic function includes:
1. Booting Device. 2. Date & Time.
3. Floppy Drive, Size and Type 4. Hard Disk size.
5. Password. 6. POST
These are the basic functions of the bios software.
BIOS
The name pretends that the battery which supplies DC Power to the bios IC known as Bios Battery.
WHY BIOS CHIP (IC) NEED
We know that the bios controlles the basic function of the computer i.e., the information about he hardware is set in the bios e.g., Date & Time, Booting Device Size of hard Disk, Flopppy Drive Size & Type, Passward etc. When we swtich off our computer the settled information is sustained stored in the Bios Chip with the help of battery. Therefore our computer bios chipa Need battery. And is called i.e., Bios is battery operated.
I Short the battery is used to store the computer hardware information in the bios chip when computer is switched off.
POWER ON SELF TEST
As the above words pretends ( ) so when computer is switched ON. It Starts booting means starts loading the operating system, but before the loading the operating system the computer test some things this test is carried out by the bios software stored in the IC. This test of the computer is called as power ON self test.
This test (POST) starts as we switch ON the computer first it test the VGA/AGP Card and the information of VGA/AGP is displayed on the screen. Then it detect the CPU Clock and the clock speed is displayed on the screen.
Then it confirm the RAM and count the RAM quantity. After that it detect thedevices like hard disk drive, CD ROM drive as.
IDE 1 Primary Master. Quantom Fir ball
IDE 1 Primary slave
IDE 2 Secondary Master 50X ATAPI CD Rom
IDE 2 Secondary Slave.
Then the floppy disk drive. During the above, IF ERROR IS NOT FOUND the computer search the booting device which will be set in the BIOS. And accoridng to that setting the computer will start loading the operating system. A message is displayed IF ERROR IS FOUND press F1 to continue/Resume Delete Key to Enter setup. The computer stops at this point. So then we enters the Bios and then Exit the Bios with saving changes and continue.
BOOTING
When we switch ON the computer it starts the process of loading an operating system and at last the OS screen appears. The OS may be Dos, Windows. The process from switch ON to welcome screen is called as booting.
BOOTING FROM HARD DISK:
Condition 1: Operating System is installed e.g., Win98 when we start the computer such that the operating system is e.g., Win98 is already installed in the hard disk what will happen.
Switch ON Boot from Hard Disk OK Welcome to Windows 98. So the computer loaded the operating system which is Win988 from the hard disk so we can say the computer has completed booting from the hard disk. The process of loading Windows 98 is called as booting. The time taken for loading Windows 98 is called as booting time.
Condition 2: When operating System is not installed in the hard disk.
Switch ON Tries to load operating system Sector not found
Boot failure Non/Invalid System disk replace and enter.
BOOTABLE:
Every media from which the computer can load the operating system e.g, Dos or windows is called as bootable media. When operating system is not installed in the hard disk the hard disk is non bootable when Windows or Dos is installed in the Hard disk then it becomes bootable.
ASSEMBLING OF COMPUTER
STEPS FOR ASSEMBLING:
Arrange computer components/Peripherals from A to Z i.e., Microprocessor + Microprocessor fan.
Main Board + Sound Card + Video Card/VGA Card
RAM (DIMM)
Hard Drive
Floppy Drive
Reliable casing
Keyboard + Mouse + Speakers
Fax Modem (Optional)
Video Display Terminal or Monitor
Data cables for hard Disk, CD Rom Floppy Disk
AC Power cables.
INSTALLATION OF COMPONENTS:
Fix the processor and Fan on the main board. Mount the mother board with the helkp of stanoffs and spaeers carefully. Fix the Dimm on the main board in its respective Dimm Slot i.e., Slot No. 1. Install the cards VGA/AGP/Sound Card/Modem etc. in case of plain mother board. In the end install the Hard Disk, Flopyy Disk, CD Rom in to their specific small bays with the help of screws. Connect the Floppy Drive power cable. Now connect the Hard Disk, And CD Rom Drive data cables according to pin one rule along with the Molex power connectors.
And fix the ATX Power Connector to the mother board new plug the hard disk activity LED connecter/Reset switch connector/Power LED Connector/Speaker/ON/OFF connector according to the mother board manual.
Now recheck all the connection if some mistake is found make correction and plug the keyboard mouse, Monitor and boot the system from Bootable CD Rom. Make the partitions in the Hard Disk Format the C: Drive, install the operating system/Drivers and else software's. Now your computer system is ready.
TROUBLE SHOOTING
Trouble shooting means any fault, problem occurs in the computer finding the problem, locating or removing of the problem and remaining of the problem is called as trouble shooting in the computer hardware.
1. System Dead.
2. System Starts but having problems e.g., Boot Failure, hangs at startup, having irregular Beeps.
3. The system load the operating system but some times hangs messaging press any key to contain some time screen disappears, or hardly goes to windows.
4. Picture quality is not good or bluish color overlaps over screen surface.
5. Modem installed but not connect the ISP.
SYSTEM IS DEAD:
If your system is dead it neither going to ON nor it beeps NO display + dead, we will follow the below steps. First we will check the power cable of the computer either it is OK or not IF ok then we will check the power supply.
STEPS OF CHECKING OF THE ATX POWER SUPPLY:
Disconnect all the connection from the computer components i.e., hard drive, floppy drive, Mother board and connect the green wire with adjacent so that to check the power supply. If the power supply fan ON’s giving air blows it means power supply is OK. For further conformation check the DC out put voltage with multimater if power supply is OK then proceed with the below steps. Now we will disconnect all the power connections except ATX i.e., from Hard Drive,
If the computer system starts it means the things which are disconnected from from the mother board are suspicious.
Now connect one by one of each disconnected hardware of Hard Drive, Floppy Drive, CD Rom Drive Modem any other card. So in this way we will find the problematic hardware, and the problem will be trouble shooted by replacing the defective hardware with a newer one or second hand.
If the problem persists then check the power ON switch located on the front pannel of the computer casing. Procedure disconnect the power ON button connector from the mother board and short the pins (Which are responsible to start the computer) with any conductive material e.g, like screw drives or ball pen writing edge. If the computer switched ON it means the power ON/OFF button is not working replace the power on button. Another case it the computer remains off then it means the problem lies bet either in the mother board or in the microprocessor, RAM Module.
So now we will take off the microprocessor and RAM Module and will check on the running and OK Mother board if these components (Microprocessor and RAM) worked properly it means the problem lies. In the mother board. If do not then replace with the running component any one of them. In this way we will trouble shoot the problem. If the microprocessor and RAM Modules are OK then we will trouble shoot the mother board.
STEPS:
1. Check the CLR CMOS.
2. Short circuit all capaciters of mother board.
3. Make sure all the components, cables and power connecters are fixed nice and tight.
These above steps will be followed after checking the mother board physically i.e., it should not be broken nor burnt. So check it now if yes then If not ok then consult with the bios copying personal.
2. BOOT FAILURE, HANGS AT STARTUP:
TIPS:
1. Boot the system from bootable CD Rom or bootable floppy.
2. Check the hard disk with fdisk either partitions are present or not if not the make parititons as discussed and procode with OS installation.
3. The system load the operating system but some time hangs messaging, press any key to continue.
TIPS:
1. Boot the system from CD or Floppy run Scandisk on primary Dos partition if Bad sectors are found replacd the Hard Drive.
2. If hard disk dose not contain bad sector format the hard disk and reinstall the windows.
3. If the problem persist then check the RAM module.
PICTURE QUALITY IS NOT GOOD:
The reason for the low picture quality is the low or minimum amount of V-RAM or VGA Memory. Standard VGA memory is 2MB if VGA Memory will be less then 2MB the video on the monitor will be jurkey. If it is two MB (VGA memory) then the video will be fluent. Some problems often occers while VGA may mab be two MB or greater.
SYMPTOMS:
When run the video the screen becomes bluish or all the video image looks bluish. This problem often occurs due to different types of multimedia software.
TIPS:
Remove all multimedia software start Control Pannel Add remove Programme Select the Program Remove No to all
Finish
If the problem not solved just reinstall the operating system.
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