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Pc components


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Pc components

  1. 1. PC Parts Identifying PC parts and their functions. Binumon Joseph S1 MCA No : 23 AJCE
  2. 2. Introduction  Personal Computers (PCs) and PC- based equipment are based on common hardware.  Here we’ll examine common hardware components.
  3. 3. External components  Visible to the end-user  Required for the PC to function  Consist of – Case – Monitor – Keyboard – Mouse
  4. 4. Case (we’ll look inside later)  The case is the “box” that holds the internal components of the PC. It protects those delicate components from dust and debris.
  5. 5. Monitor  The monitor is the main output component used on a PC. It’s where the computer is able to show you what it, and you, are doing.
  6. 6. Keyboard  The keyboard is the main input device you use with a computer or PC-based equipment.
  7. 7. Mouse  On any PC that uses graphics (pictures), a mouse is an essential input device that allows you to control the PC.
  8. 8. Internal Components  Remember the case? We said it contained internal components.  Internal components are the parts of the computer that do most of the work, though they are behind the scenes.  Understanding their basic functions is important to understanding the PC as a whole.
  9. 9. Internal Components  Motherboard  CPU  Drives  Expansion cards  Memory  Power supply
  10. 10. Motherboard  The motherboard (main board, system board) is a large circuit board which all other PC components connect to in some way.
  11. 11. Motherboard
  12. 12. CPU  The CPU (Central Processing Unit) is the brain of the PC. All work done by the PC involves the CPU in some way. The CPU plugs into the motherboard.
  13. 13. CPU
  14. 14. Drives  There are many kinds of drives in a computer: CDROM drives, hard drives, floppy drives, ZIP drives, tape drives, pen drives. The basic function of all drives is to store information (more on this later).
  15. 15. Hard drive
  16. 16. Floppy drive
  17. 17. CD- or DVD-ROM drive
  18. 18. RAM  Random Access Memory (RAM) is memory that the CPU uses when performing its tasks.  RAM consists of chips that plug into the motherboard.  In general, the more RAM you have, the better.
  19. 19. Expansion Cards  Expansion cards are circuit boards that plug into the motherboard to expand its capabilities. Sound cards are an example. One required expansion card is the video card, which connects to the monitor.
  20. 20. Video card  Normally an expansion card, but sometimes built into the motherboard (integrated), the video card has 15 holes, in three rows of five.
  21. 21. Power Supply  The power supply is crucial to the PC. It converts power from the wall outlet into power the PC can use. It powers all internal components, including the motherboard and drives.
  22. 22. Communication Ports  In industry, non-integrated PCs must connect to external machines, such as: – CNC machines – Automobiles – Robotic devices  These connections are made via communication ports.
  23. 23. Communication Ports  Common communication ports are: – Keyboard – Mouse – Serial – Parallel – Modem – Network Interface Card (NIC) – USB
  24. 24. Keyboard  Barcode readers often attach to keyboard ports.  Keyboard ports appear in DIN5 and PS/2 or Mini-DIN6 (below).
  25. 25. Mouse  Some input devices connect via a mouse port.  Common mouse ports are PS/2 (Mini-DIN6) on the left and serial (9 pin male) on the right.  Don’t connect a mouse-port device to a keyboard port.
  26. 26. Serial  Serial ports are fairly slow ports that can transmit data over a long distance (hundreds of feet).  Serial ports are either 9 or 25 pin.  Serial ports are male (plugs) on the PC.
  27. 27. Parallel  Parallel ports are normally used for output to printing devices.  Parallel ports are 25 pin female (socket) on the PC.
  28. 28. Modem  Modems are normally expansion cards that contain two phone jacks.  They communicate via phone lines to remote devices.
  29. 29. Network Interface Card (NIC)  NICs are expansion cards that connect PC devices to networks via special network cable.  Many connections to external machines are now made via NICs, which normally have one port.
  30. 30. USB  A popular technology to connect to external devices is USB, which can support 127 devices.  USB will eventually replace keyboard, serial, and parallel ports.
  31. 31. Compare Communications Ports  Parallel is normally used for output only.  Keyboard and mouse ports are normally input only.  Serial, NIC, Modem and USB are bi- directional (input and output).
  32. 32. Storage Devices  Storage is easiest to think of in terms of primary and secondary.  Primary storage is used by the CPU. The primary example is RAM. Primary loses information without power.  Secondary devices can store data without power. Drives are the main secondary storage devices.
  33. 33. 3.5 inch floppy drive
  34. 34. Hard drive
  35. 35. CDROM drive
  36. 36. Storage Reminders  RAM stores information that is currently active.  Information in RAM must be saved to secondary storage or it will be lost when power is removed.  Secondary storage keeps data unless the user removes it (or the device fails).
  37. 37. RAM vs. ROM  RAM stands for Random Access Memory  RAM changes constantly as the CPU needs different items in memory based on the user’s requests.  RAM is lost when power is removed.
  38. 38. ROM •ROM stands for Read Only Memory •ROM does not change. •ROM is not lost when the power is removed from a PC. •ROM stores key instructions that the computer needs to boot up and operate.
  39. 39. Computer Hardware Components – How did the computer become known as the stored-program computer? • Do they all have the same characteristics? – Memory on chips and memory on magnetic media, how do they differ? – What do you look for when comparing memory devices? – How is information moved around within the computer? – How can you help your computer run better?
  40. 40. Basic Concepts of Computer Hardware  This model of the typical digital computer is often called the von Neumann computer. – Programs and data are stored in the same memory: primary memory. – The computer can only perform one instruction at a time. CPU (Central Processing Unit) Input Units Output Units Primary Memory
  41. 41. Basic Concepts of Computer Hardware  Input/Output (I/O): Refers to the process of getting information into and out of the computer. – Input: Those parts of the computer receiving information to programs. – Output: Those parts of the computer that provide results of computation to the person using the computer.
  42. 42. Sources of Data for the Computer  Two types of data stored within a computer: – Original data or information: Data being introduced to a computing system for the first time. • Computers can deal directly with printed text, pictures, sound, and other common types of information. – Previously stored data or information: Data that has already been processed by a computer and is being stored for later use. • These are forms of binary data useful only to the computer. • Examples: Floppy disks, DVD disks, and music CDs.
  43. 43. Input Devices  Two categories of input hardware: – Those that deal with original data. – Those that handle previously stored data.
  44. 44. Input Devices  Input hardware: Those that deal with original data. – Keyboard – Mouse – Voice recognition hardware – Scanner – Digital camera  Digitizing: The process of taking a visual image, or audio recording and converting it to a binary form for the computer. – Used as data for programs to display, play or manipulate the digitized data.
  45. 45. Input Devices  Connecting Hardware to the computer: – Hardware needs access through some general input/output connection. • Port: The pathway for data to go into and out of the computer from external devices such as keyboards. – There are many standard ports as well as custom electronic ports designed for special purposes. – Ports follow standards that define their use. » SCSI, USB: Multiple peripheral devices (chain). » RS-232, IDE: Individual peripheral devices. • Peripheral device: A piece of hardware like a printer or disk drive, that is outside the main computer.
  46. 46. Input Devices  Connecting Hardware to the computer: (continued) – Hardware needs software on the computer that can service the device. • Device driver: Software addition to the operating system that will allow the computer to communicate with a particular device.
  47. 47. Input Devices  Common Basic Technologies for Storing Binary Information: – Electronic – Magnetic – Optical
  48. 48. Input Devices  Electronic Circuits – Most expensive of the three forms for storing binary information. – A flip-flop circuit has either one electronic status or the other. It is said to flip-flop from one to the other. – Electronic circuits come in two forms: • Permanent • Non-permanent
  49. 49. Input Devices  Magnetic Technology – Two parts to most of the magnetic forms of information storage: • The medium that stores the magnetic information. – Example: Floppy disk. Tiny spots on the disk are magnetized to represent 0s and 1s. • The device that can “read” that information from the medium. – The drive spins the disk. – It has a magnetic sensing arm that moves over the disk. – Performs nondestructive reading.
  50. 50. Input Devices  Optical – Uses lasers to “read” the binary information from the medium, usually a disc. • Millions of tiny holes are “burned” into the surface of the disc. • The holes are interpreted as 1s. The absence of holes are interpreted as 0s.
  51. 51. Input Devices  Secondary Memory Input Devices – These input devices are used by a computer to store information and then to retrieve that information as needed. • External to the computer. • Commonly consists of floppy disks, hard disk drives, or CD-ROMs. – Secondary memory uses binary. • The usual measurement is the byte. – A byte consists of 8 binary digits (bits). The byte is a standard unit.
  52. 52. Input Devices  The four most important characteristics of storage devices: – Speed and access time – Cost / Removable versus non-removable – Capacity – Type of access
  53. 53. Input Devices  Speed (Access time) - How fast information can be taken from or stored onto the computer memory device’s medium. – Electronic circuits: Fastest to access. • 40 billionths of a second. – Floppy disks: Very slow in comparison. • Takes up to 1/2 second to reach full speed before access is even possible.
  54. 54. Input Devices  Cost – Megabyte: A Million bytes. – Gigabyte: A billion bytes. – Two parts to a removable secondary storage device: • The cost of the medium. (Cheaper if bought in quantity) • The cost of the drive. Examples: Cost for drive Cost for medium Floppy drive (1.4MB) 59.00 .50 Zip 100 (100 MB) 99.00 10.00 CD-WR (650 MB) 360.00 and up 1.00
  55. 55. Input Devices  Capacity - The amount of information that can be stored on the medium. Unit Description Approximate Size 1 bit 1 binary digit 1 nibble 4 bits 1 byte 8 bits 1 character 1 kilobyte 1,024 bytes ≈1/2 page, double spaced 1 megabyte 1,048,576 bytes ≈500,000 pages 1 million bytes 1 gigabyte 1,073,741,824 bytes ≈5 million pages 1 billion bytes 1 terabyte 1 trillion bytes ≈5 billion pages
  56. 56. Input Devices  Type of Access • Sequential - Obtained by proceeding through the storage medium from the beginning until the designated area is reached (as in magnetic tape). • Random Access - Direct access (as in floppy and hard disks).
  57. 57. Primary Memory  Primary storage or memory: Is where the data and program that are currently in operation or being accessed are stored during use. – Consists of electronic circuits: Extremely fast and expensive. – Two types: • RAM (non-permanent) – Programs and data can be stored here for the computer’s use. – Volatile: All information will be lost once the computer shuts down. • ROM (permanent) – Contents do not change.
  58. 58. The Central Processing Unit  The Central Processing Unit ( CPU) – Often referred to as the “brain” of the computer. – Responsible for controlling all activities of the computer system. – The three major components of the CPU are: 1. Arithmetic Unit (Computations performed) Accumulator (Results of computations kept here) 2. Control Unit (Has two locations where numbers are kept) Instruction Register (Instruction placed here for analysis) Program Counter (Which instruction will be performed next?) 3. Instruction Decoding Unit (Decodes the instruction) – Motherboard: The place where most of the electronics including the CPU are mounted.
  59. 59. Output Devices  Output units store and display information (calculated results and other messages) for us to see and use. – Floppy disk drives and Hard disk drives. – Display monitors: Hi-resolution monitors come in two types: • Cathode ray tube (CRT) - Streams of electrons make phosphors glow on a large vacuum tube. • Liquid crystal display (LCD) - A flat panel display that uses crystals to let varying amounts of different colored light to pass through it. – Developed primarily for portable computers.
  60. 60. Output Devices  Audio Output Devices – Windows machines need special audio card for audio output. – Macintosh has audio playback built in. – Audio output is useful for: • Music – CD player is a computer. – Most personal computers have CD players that can access both music CDs and CD-ROMs. • Voice synthesis (becoming more human sounding.) • Multimedia • Specialized tasks (i.e.: elevator’s floor announcements)
  61. 61. Output Devices  Optical Disks: CD-ROM and DVD – CD-ROM (Compact Disk - Read Only Memory) • By its definition, CD-ROM is Read Only. • Special CD drives “burn” information into blank CDs. – Burn: A laser is used to “burn” craters into the surface to represent a binary 1. – Two main types of CDs: » CD-R (Compact Disk - Recordable) » CD-WR (Compact Disk - ReWritable) • It takes longer to write to a CD-R than a hard drive. • Special software is needed to record.
  62. 62. Output Devices  DVD (Digital Versatile Disk) – Allows up to 17 gigabytes of storage (from 4.7 GB to 17 GB). – Compatible with older CD-ROM technology. – The four versions of the DVD:
  63. 63. Output Devices  Storage Requirements: How much storage capacity is needed for… – One keystroke on a keyboard. 1 byte (8 bits) – One page single-spaced document. 4.0 K – Nineteen pages formatted text. 75 K – One second of high-fidelity sound. 95-110 K – Complete word processing program. 8.4 MG  Storage Capacity: How much data can be stored on… – One inch of 1/2 in. wide magnetic tape. 4 K – One 3 1/2” floppy disk, high density. 1.4 MG – One Compact Disk. 650 MG – One DVD. up to 17 GB
  64. 64. Moving Information Within the Computer  How do binary numerals move into, out of, and within the computer? – Information is moved about in bytes, or multiple bytes called words. • Words are the fundamental units of information. • The number of bits per word may vary per computer. • A word length for most large IBM computers is 32 bits:
  65. 65. Moving Information Within the Computer  Bits that compose a word are passed in parallel from place to place. – Ribbon cables: • Consist of several wires, molded together. • One wire for each bit of the word or byte. • Additional wires coordinate the activity of moving information. • Each wire sends information in the form of a voltage pulse.
  66. 66. Moving Information Within the Computer  Example of sending the word WOW over the ribbon cable – Voltage pulses correspondi ng to the ASCII codes would pass through the cable.
  67. 67. Packaging the Computer  The many physical forms of the general purpose computer: – All follow general organization: • Primary memory • Input units • Output units • Central Processing Unit – Grouped according to speed, cost, size, and complexity. Super Computers Mainframe Computers Minicomputers Microcomputer Palmtop Computer Calculator Fast Expensive Complex Large Slow Cheap Simple Small
  68. 68. Software Tools for Maintaining Your Computer Hardware  Utility Programs exist that can help diagnose and solve computer hardware problems. – Four major problem areas where utility programs are helpful: • Finding and fixing problems. – Testing Input/Output peripherals. – Testing RAM, motherboard, video cards. – Recovering deleted files or fixing damaged disks. • Improving computer performance. – De-fragmenting a disk (Packs all files closer together). • Preventative maintenance. • Troubleshooting. – Locates incompatible programs.
  69. 69. Overview  The PC consists of common external and internal components.  Each component has a specific task.  Communication ports connect to external devices.  Storage devices are classified and primary or secondary.
  70. 70. Thank You…