COMPUTER HARDWARE SERVICING NC IIModule by: Michelle Angela M. Moleta, MIT(CAR), PCO Assessor, CHS Assessor

The COMPUTER HARDWARE SERVICING NC II Qualification consists of competencies that must possess to enable to diagnose and troubleshoot problems in personal computer systems, software, replace parts and get the system back to normal operation. A person who has achieved this Qualification is competent to be: Computer Service Technician Computer Repairman This Qualification is packaged from the competency map of the Information and Communication Technology (ICT) Industry as shown in Annex A. The units of competency comprising this qualification include the following: Code 500311105 500311106 500311107 500311108 BASIC COMPETENCIES Participate in workplace communication Work in a team environment Practice career professionalism Practice occupational health and safety procedures

CODE ICT315202 ICT311201 ELC311201 ELC311202 ELC724201 ELC724202

COMMON COMPETENCIES Apply quality standards Perform computer operations Perform mensuration and calculation Prepare and interpret technical drawing Use hand tools Terminate and connect electrical wiring and electronic circuits CORE COMPETENCIES Install computer systems and networks Diagnose and troubleshoot computer systems Configure computer systems and networks Maintain computer systems and networks

CODE ELC724318 ELC724319 ELC724320 ELC724321

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Module 1-Introduction What is a Computer? It is an electronic device capable of performing its prescribed operations. The four basic categories of computers are: 1. Microcomputer (PC) - a small desktop or laptop. Referred to as a typical desktop personal computer (PC). 2. Minicomputers - Mid-size computers, non-portable types. They often appear as mainframes. They are gradually disappearing from the marketplace. 3. Mainframe Computers - These are large computers, often occupying a large room. They are generally used by banks, universities, and some government functions such as IRS, etc. 4. Supercomputers - The most powerful computers. They are very fast, and have extremely high storage capacity, probably in the terrabyte range. Used in research, weather forecasting, modeling/simulations, etc. Microcomputer (PC) PC (Personal Computer) is the most common category of computers. This would include your home PCs and most of your business class PCs Workstations is a breed of computer which is a high performance version of the PC Laptops are portable computers (also referred to as notebooks) Servers is a machine developed to allow for file or print serving, application hosting, or some other task usually involving many simultaneous connections SYSTEM - is a collection of elements or parts that work together as a unit to solve a specific problem Three Basic Components of a Computer System: HARDWARE - are the physical devices of a computer, - it is composed of the mechanical and electronic components that make up the computer system. Functional Parts of the Hardware: Input Unit o Allows the user to communicate with the computer o Used to Enter data and instructions Keyboard, touch screen, Digital Camera, Pointing Device (Mouse, Trackball, Trackpoint, Touchpad, Joystick, light Pen) , Scanning Device (Image Scanner, Bar Code Reader, optical Mark Reader, Magnetic Stripes Reader) Central Processing Unit o Also known as the CPU o Carries out all instructions Microprocessor is the center of the modern computer, it is an integrated circuit or microchip that contains the entire CPU of a computer Output Unit o Enables the computer to present information to the user o Translates the results of computer processing into a form that one can use or work with, like a printout or a picture displayed on the computers screen2

Monitor, Video Adapter, Printer, Speaker Storage Unit o Used to hold or store large volumes of data temporarily or permanently on a magnetic or optical disks Primary Memory, Secondary Memory (Floppy Disk, CD-ROM, DVD-ROM, Memory Stick) SOFTWARE - the programs that run the computer Program - is a set of instructions that tells the computer what to do in order to generate the desired output 1. Programming Language Software An artificial language used to define the step-by-step instructions that can be processed and executed by the computer Used to create system and application programs 2. System Software Refers to the Operating System and utility programs that manage computer resources Controls the standard activities or operations inside the computer and directs the computer how to operate its hardware resources 3. Application Software Are programs used to solve specific processing problems Are used in order to be productive and efficient in doing the work in school, in the office and in any business or personal transactions PEOPLEWARE - are the ones who develop the system, they are the personnel involved in the computer system 1. Technical Users The ones who design and implement or carry out the system Systems Analyst Computer Programmers Systems Engineers Application Developers Computer Technicians 2. Users or End-Users Are the primary operators of the computer and are the ones who enter the data into the computer Data encoders Computer operators Computer hobbyists Application users PC Connections A typical computer connects to the world around it in three different ways: Input / Output Ports Parallel - This port is commonly used to connect a printer Serial - This port is typically used to connect an external modem.3

Universal Serial Bus (USB) - Quickly becoming the most popular external connection, USB ports offer power and versatility and are incredibly easy to use. Internet / Network Modem (from modulator-demodulator) - This is the standard method of connecting to the Internet; it modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. Local area network (LAN) card - This is used by many computers to connect to each other Cable modem - This type of modem uses the cable TV system in your home to connect to the Internet Digital Subscriber Line (DSL) modem - This is a high-speed connection that works over a standard telephone line.

The MOST common components in a Personal Computer (PC) are: Motherboard This is the main circuit board that all of the other internal components connect to. The CPU and memory are usually on the motherboard. Other systems may be found directly on the motherboard or connected to it through a secondary connection Power supply An electrical transformer regulates the electricity used by the computer. Pin 1 2 3 4

Wire Color Yellow Black Black Red

Signal +12v Ground Ground +5v

Storage Devices This is a hardware device designed to store information Two types of Storage Device: Primary Memory - also known as main memory, are responsible for holding instructions and data to provide the rapid access to central processing unit SecondaryMemory External Memory - Stores data externally using a device/medium CPU (Central Processing Unit) The BRAIN of a Computer System RAM (Random Access Memory) is the place in a computer where the operating system, application programs, and data in current use are kept so that they can be quickly reached by the computer's processor. Expansion Slots This is located inside a computer on the motherboard or riser board that allows additional boards to be connected to it Common Types AGP Short for Accelerated Graphics Port, an advanced port designed for Video cards and 3D accelerators4

ISA Short for Industry Standard Architecture, ISA is a standard of computer bus PCI Peripheral Component Interconnect, PCI was originally developed by Intel as an expansion to the ISA bus

Expansion Card This is a printed circuit board that can be inserted into an expansion slot of a computer motherboard to add additional functionality to a computer system Sound card - This is used by the computer to record and play audio

by converting analog sound into digital information and back again. Graphics card - This translates image data from the computer into a

format that can be displayed by the monitor. Local area network (LAN) card - This is used by many computers to connect to each other (also known as the Network Adapter or Network Interface Card) SCSI - Pronounced "scuzzy," the small computer system interface is a method of adding additional devices, such as hard drives or scanners, to the computer.

Cache Memory BIOS provides a definition of the system for booting CMOS Keyboard the most common input device composed of alphanumeric keys used to input data/commands Common Types: PS1 PS2 USB Wireless Monitor the most common output device, all output that can be seen through the monitor is called a soft copy "CHIPSET" It controls most of the capabilities such as type of memory, I/O, etc. Operating System This is the basic software that allows the user to interface with the computer. Application Software Are programs used in order to be productive and efficient in doing the work in school, in the office and in any business or personal transactions Person to operate it. The Peopleware5

Other motherboard components that also serves specific functions: BUS - connects all the components of the computer and provides a path from device/controller to the next component. Expansion Slots - Memory Slots - provides receptacles for adding additional memory chips (SIMMs, DIMMs, or other types of memory). ZIF Socket - provides a location to insert the heart of the computer - the CPU. USB Port - some newer machines will have a port for the Universal Serial Bus (USB) connection. FAN A computer fan can be any fan inside a computer case used for cooling purposes, and may refer to fans that draw cooler air into the case from the outside, expel warm air from inside, or move air across a heat sink to cool a particular component. CABLE (Data Cable) (called ata cables or serial or SCSI) simply transfer data from one device to the motherboard inside or even to another device hooked up to the same cable. Integrated Drive Electronics (IDE) Controller - This is the primary interface for the hard drive, CD-ROM and floppy disk drive. PC: The Absolute Basics computers operate using electrical current to represent "states" in the computer characters, numbers, and symbols are represented by a number of binary bits How is a computer instruction executed?

1 Fetch 3 Execute 2 Decode

Fetch Cycle - gets the next instruction to be executed into a register. Decode Cycle - break down the instruction to see what to do. Execute Cycle - do the thing the instruction is supposed to do.

Conversion Units 1 byte = 8 bits 1 kilobyte (K / Kb) = 1,024 bytes 1 megabyte (M / MB) = 1,048,576 bytes 1 gigabyte (G / GB) = 1,073,741,824 bytes 1 terabyte (T / TB) = 1,099,511,627,776 bytes 1 petabyte (P / PB)= 1,125,899,906,842,624 bytes 1 exabyte (E / EB) = 1,152,921,504,606,846,976 bytes Safety Tips Electrical safety 1.) To prevent electrical shock hazard, disconnect the power cable from the electrical outlet before relocating the system. 2.) When adding or removing devices to or from the system, ensure that the power cables for the devices are unplugged before the signal cables are connected. If possible, disconnect all power cables from the existing system before you add a device. 3.) Before connecting or removing signal cables from the motherboard, ensure that all power cables are unplugged.6

Seek professional assistance before using an adapter or extension cord. These devices could interrupt the grounding circuit. 5.) Make sure that your power supply is set to the correct voltage in your area. If you are not sure about the voltage of the electrical outlet you are using, contact your local power company. 6.) If the power supply is broken, do not try to fix it by yourself. Contact a qualified service technician or your retailer.4.)

Operation safety 1.) Before installing the motherboard and adding devices on it, carefully read all the manuals that came with the package. 2.) Before using the product, make sure all cables are correctly connected and the power cables are not damaged. If you detect any damage, contact your dealer immediately. 3.) To avoid short circuits, keep paper clips, screws, and staples away from connectors, slots, sockets and circuitry. 4.) Avoid dust, humidity, and temperature extremes. Do not place the product in any area where it may become wet. 5.) Place the product on a stable surface. 6.) If you encounter technical problems with the product, contact a qualified service technician or your retailer. The Computer Cabling Basic operations Power cord plugged in. (If plugged into a power strip, turn it on. Includes peripherals.) Cables to peripherals secure. Power on peripherals. Power on the system. Observe the system for proper operation. Note: For items in or attached to a system to work properly they must be securely connected. Be sure to carefully connect the cables and power cord.

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