1. The Visible PC
Chapter 2

2. Overview In this chapter, you will learn to Describe how the PC works
Identify the essential tools of the trade and avoid electrostatic discharge (ESD)
Identify the major internal and external components of a PC
Identify the different connectors on a typical PC system unit
Instructor Tip
When gaining attention and establishing common ground, ask questions such as, “Who here has experience working on computers?”
For a WIIFM statement, share a real-life experience in which knowledge of this topic made your job easier: For example: “When working on computers, one of the most important things you need to know is which component is which once you open it up. If you’re having problems with the video card, there’s no point in trying to repair the network interface card. In this topic, you’ll learn about some of the tools we use, the internal components of the PC, and many of the connectors.”
The pre-tests are designed to give you an indication of how much prior knowledge your students have brought to this class. They are meant to be used for class discussion, rather than as real tests. As such, only a few questions are included in each test and the “correct” answers are not provided. You can use pre-tests to gain a rapport with your students and measure how much time you might need to take on a particular subject.

3. How the PC Works
Output
Input
Processing

4. How the PC Works Software Hardware
Operating system (Windows, MAC OS X, Linux)
Applications (PowerPoint, Word, Outlook, Internet Explorer)
Hardware
Pieces you can touch (mouse, monitor, motherboard, etc.)

5. How the PC Works Computer functions through four stages:
Input provides the computer with data
Keyboard and mouse
Processing occurs when the computer processes or manipulates your data
Output is provided as the result of processing your data
Monitor, printer, speakers
Storage is how you keep your data for later use
Hard drive, CD-ROM disc, floppy diskette

6. X How the PC Works The Art of the PC Technician Broken PC PC tech
Hardware and software interact to accomplish the four stages
Your goal is to understand all the parts and how they interact in the various stages
By understanding how it works, you’re better able to fix it when it breaks X
Broken PC
PC tech
Fixed PC

7. Tools of the Trade and ESD Avoidance

8. PC Tool Kit The basic tech toolkit: a Phillips-head screwdriver
Most toolkits contain a few other items
It’s a good idea to include
Magnifying glass
Small flashlight

9. CompTIA A+ Essentials
IT Essentials

10. Electrostatic Discharge
Electrostatic discharge (ESD) is the passage of a static electrical charge into your PC or a PC component such as a RAM stick
Static electricity can destroy sensitive parts of a PC
ESD damage is much more prevalent in dry, cool environments

11. Anti-static Tools Anti-static wrist strap Anti-static mats
Keeps you and the PC at the same electrical potential to prevent ESD
Anti-static mats
Used temporarily to place parts taken out of your PC
Anti-static bags
Used to store electrical components from your PC
Always unplug a PC when you work on it. Don’t just turn it off.
Static electricity, and therefore the risk of ESD, is much more prevalent in dry, cool environments.

12. The Complete PC

13. External Connections Plug goes into a port Port/jack accepts a plug
Connector can be either a port or a plug

14. DIN Connectors DIN connectors are round and come in two sizes:
Mini-DIN
Always a female connector
Used frequently by a keyboard or mouse

15. USB Connectors Universal Serial Bus (USB) Used by many devices today
Devices are hot-swappable
You can insert or remove the device while the PC is powered on
USB B plugs into devices
USB A plugs into computers
USB B
USB A
Discussion Point
USB
Standard USB, designed by Intel, runs at about 1.5 Mbps. USB2, a newer standard, is backwardly compatible to standard USB, but promises to run at 480 Mbps. For a variety of reasons, USB2 is unlikely to reach these speeds, and it does not perform to FireWire (IEEE 1394) standards.

16. FireWire Connectors
FireWire connectors move data at incredibly high speeds
Also known as IEEE 1394
Popular with video applications
Uses 6-wire connector (note the rounded edge)
Hot-swappable

17. DB Connectors DB connectors have a slight D-shape
Male DB connectors have pins
Female DB connectors have sockets
Oldest type of connector in the PC

18. RJ Connectors Registered jack or RJ connectors
RJ-11 used by telephone lines
RJ-45 used in network interface cards (NICs)
Discussion Point
Registered jacks
RJ-11 and RJ-45 are just two of the many RJ specifications listed in the U.S. Federal Communications Commission Rules and Regulations, 47CFR (Code of Federal Regulations), Part 68. The number following the “RJ” is assigned by the FCC and indicates the usage of the jack. In Europe, these connectors are generally called “Western Electric” or “Western” plugs and sockets. In North America, they are called “RJ” or “modular” connectors.

19. Audio Connectors Audio connectors are used on sound cards
Used to connect speakers, microphones, and other audio devices

20. Devices and Their Connectors

21. Cards vs. Onboard Connectors exposed on rear and front of PCs
Some connectors attach directly to motherboard
Some connectors attach to boards that plug into motherboard

22. Keyboard
Keyboards connect into dedicated mini-DIN (usually purple) or USB
Plugs and ports usually purple

23. Video Cards Video cards connect to monitors S-Video connector (left)
Digital video interface (DVI) connector (center)
15-pin female DB connector (right)
Newer High-Definition Multimedia Interface (HDMI)
Many video cards come with multiple connectors. These are to support video input/output or for a second monitor.

24. Sound Cards Sound cards Convert digital information into sound
Convert sound from a microphone into digital data
Mini-audio jacks for speakers and microphones
DB-15 connector for a joystick or musical instrument
Newer Sony/Phillips Digital Interface Format (S/PDIF)

25. Network Cards Networks: groups of PCs connected together
Network interface cards (NICs) typically on motherboard (can be expansion card)
Typical connector is RJ-45

26. Mouse A mouse enables you to select graphical items on a screen
Connects through mini-DIN port (usually light green) or USB port (most common)
Trackball may be used instead of mouse

27. Modem
Modems convert analog telephone signals into digital data and vice versa
Internal modems are expansion cards
External modems connect to a serial port
Uses two RJ-11 sockets
One to the telephone jack in the wall
One to a telephone if you wish
The RJ-11 connectors on a modem look very similar to the RJ-45 connectors on a network card. Compare the graphic of the RJ-45 connector to the RJ-11 connector—could you tell the difference?

28. Serial Ports Serial ports are used to add external devices to a PC
Accept and transmit serial data
Male DB-9 or DB-25
Largely replaced by USB
Serial ports are one of the few connectors on modern systems that were also used in the first PCs decades ago!

29. Printer Printers output data from the PC onto paper
Historically used a female DB-25
Today printers almost exclusively use a USB or FireWire port

30. Joystick
Joysticks are used almost exclusively to play games on the computer
Originally designed as an input device to be used like a mouse
Connector typically orange
Most joysticks now use USB

31. Inside the System Unit

32. Case The case houses all of the internal components
Protects internal components
External connections in front and rear
Provides access to storage devices such as CDs

33. CPU Central processing unit (CPU) Also called a microprocessor
Performs calculations
CPUs generate a lot of heat
Cooling fan and/or heat sink used to keep them cool

34. CPU Makes CPUs come in different packages Models Intel AMD
Pin grid array (PGA)
Most common today
Models
Celeron
Athlon
Sempron
Pentium

35. RAM Random access memory (RAM)
Stores programs and data currently used by the CPU
Measured in megabytes (MB) and gigabytes (GB)
Each piece or module of RAM is called a stick
Dual inline memory module (DIMM) most common today

36. Motherboard The motherboard is a thin, flat piece of circuit board
Everything connects directly or indirectly to the motherboard
Contains sockets for the CPU, RAM, power, and external devices such as mice, printers, and keyboards
Expansion slots allow the addition of new components
Discussion Point
Motherboard tracings
Motherboards today can contain as many as seven layers of tracings sandwiched inside the board. Once a motherboard is cracked, it cannot be repaired.

37. Power Supply Provides electrical power to PC components
Uses 110VAC power from the wall outlet
Has power connectors for the motherboard and other devices
Uses a fan to keep itself and the PC cool inside
Safety Alert
High voltage capacitor holds power after unplugged
Safety Alert
Never open up a power supply. There are no serviceable parts (except the cooling fan) inside a power supply that are covered within the scope of this coursework. Like a monitor, a power supply contains a high voltage capacitor that can hold high voltage for a very long time after being powered down.

38. Floppy Drive The floppy drive uses floppy diskettes to store data
Connects to the computer via a ribbon cable
Connects to the floppy controller on the motherboard
Uses a connector from the power supply

39. Hard Drive
Hard drives store programs and data not currently in use by the CPU
Capacity quoted in megabytes (MB) or gigabytes (GB)
A typical PC has one hard drive but may contain more
Common types include
Parallel AT attachment (PATA)
Serial AT attachment (SATA)
Small computer system interface (SCSI)
Uses a power cable from the power supply 39

40. Optical Media Two groups CD DVD Stores about 700 MB CD-ROM (read only)
CD-R, CD-RW (allows writing to CD)
DVD
Stores about 4 GB of data
DVD-ROM, DVD+R, DVD-R, DVD+RW, DVD-RW
There are a number of writable DVD standards with names like DVD-RW or DVD+ RW. The DVD industry is still fighting to see which will become dominant.