Discovering Computers Fundamentals, 2010 Edition
Living in a Digital World Objectives Overview
Differentiate among various Describe the control unit styles of system units on and arithmetic logic unit desktop computers, components of a processor, notebook computers, and and explain the four steps in mobile devices a machine cycle
Define a bit and describe Differentiate among the how a series of bits various types of memory represents data
See Page 155 Discovering Computers Fundamentals, 2010 Edition 2 for Detailed Objectives Chapter 4 Objectives Overview
Differentiate between a Describe the purpose port and a connector, and types of expansion and explain the slots and adapter cards differences among a USB port and other ports
Understand how to clean Describe the types of a system unit on a buses in a computer computer or mobile device
See Page 155 Discovering Computers Fundamentals, 2010 Edition 3 for Detailed Objectives Chapter 4 The System Unit
• The system unit is a case that contains electronic components of the computer used to process data
Page 156 Discovering Computers Fundamentals, 2010 Edition 4 Figure 4-1 Chapter 4 The System Unit
• The inside of the system unit on a desktop personal computer includes:
Drive bay(s)
Power supply
Sound card
Video card
Processor
Memory
Page 157 Discovering Computers Fundamentals, 2010 Edition 5 Figure 4-2 Chapter 4 The System Unit
• The motherboard is the main circuit board of the system unit – A computer chip contains integrated circuits
Page 158 Discovering Computers Fundamentals, 2010 Edition 6 Figure 4-3 Chapter 4 Processor
• The processor , also called the central processing unit (CPU ), interprets and carries out the basic instructions that operate a computer – Contain a control unit and an arithmetic logic unit (ALU) Multi-core Dual-core Quad-core processor processor processor
Page 159 Discovering Computers Fundamentals, 2010 Edition 7 Chapter 4 Processor
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click Multi-Core Processors below Chapter 4 Page 159 Discovering Computers Fundamentals, 2010 Edition 8 Figure 4-4 Chapter 4 Processor
• The control unit is the component of the processor that directs and coordinates most of the operations in the computer • The arithmetic logic unit (ALU) performs arithmetic, comparison, and other operations
Pages 159 - 160 Discovering Computers Fundamentals, 2010 Edition 9 Chapter 4 Processor
• For every instruction, a processor repeats a set of four basic operations, which comprise a machine cycle
Page 160 Discovering Computers Fundamentals, 2010 Edition 10 Figure 4-5 Chapter 4 Processor
The system clock controls the timing of all computer operations •The pace of the system clock is called the clock speed , and is measured in gigahertz (GHz )
Pages 160 - 161 Discovering Computers Fundamentals, 2010 Edition 11 Chapter 4 Data Representation
Most computers are digital
Digital signals are in one of two states: on or off • Most computers are digital • The binary system uses two unique digits (0 and 1) • Bits and bytes
Page 162 Discovering Computers Fundamentals, 2010 Edition 12 Chapter 4 Data Representation
A computer circuit represents Eight bits grouped together as a the 0 or the 1 electronically by unit are called a byte. A byte the presence or absence of an represents a single character in electrical charge the computer
Page 162 Discovering Computers Fundamentals, 2010 Edition 13 Figures 4-6 – 4-7 Chapter 4 Data Representation
• ASCII (American Standard Code for Information Interchange) is the most widely used coding scheme to represent data
Page 162 Discovering Computers Fundamentals, 2010 Edition 14 Figure 4-8 Chapter 4 Data Representation
Page 163 Discovering Computers Fundamentals, 2010 Edition 15 Figure 4-9 Chapter 4 Memory
• Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data • Stores three basic categories of items:
Data being The operating Application processed and the system and other programs resulting system software information
Page 163 Discovering Computers Fundamentals, 2010 Edition 16 Chapter 4 Memory
• Each location in memory has an address • Memory size is measured in kilobytes (KB or K), megabytes (MB ), gigabytes (GB ), or terabytes (TB )
Page 164 Discovering Computers Fundamentals, 2010 Edition 17 Figure 4-11 Chapter 4 Memory
• The system unit contains two types of memory:
Volatile memory Nonvolatile memory
Loses its contents when Does not lose contents power is turned off when power is removed
Examples include ROM, Example includes RAM flash memory, and CMOS
Pages 164 - 165 Discovering Computers Fundamentals, 2010 Edition 18 Chapter 4 Memory
Page 165 Discovering Computers Fundamentals, 2010 Edition 19 Figure 4-12 Chapter 4 Memory
• Three basic types of RAM chips exist:
Dynamic RAM Static RAM (SRAM) (DRAM)
Magnetoresistive RAM (MRAM)
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click RAM below Chapter 4 Page 166 Discovering Computers Fundamentals, 2010 Edition 20 Chapter 4 Memory
• RAM chips usually reside on a memory module and are inserted into memory slots
Page 166 Discovering Computers Fundamentals, 2010 Edition 21 Figure 4-13 Chapter 4 Memory
• The amount of RAM necessary in a computer often depends on the types of software you plan to use • Memory cache speeds the processes of the computer because it stores frequently used instructions and data
Pages 166 - 167 Discovering Computers Fundamentals, 2010 Edition 22 Chapter 4 Memory
Read-only memory (ROM ) refers to memory chips storing permanent data and instructions •Firmware
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click ROM below Chapter 4 Page 167 Discovering Computers Fundamentals, 2010 Edition 23 Chapter 4 Memory
• Flash memory can be erased electronically and rewritten – CMOS technology provides high speeds and consumes little power
Pages 167 – 168 Discovering Computers Fundamentals, 2010 Edition 24 Figure 4-14 Chapter 4 Memory
• Access time is the amount of time it takes the processor to read from memory – Measured in nanoseconds
Page 168 Discovering Computers Fundamentals, 2010 Edition 25 Figures 4-15 – 4-16 Chapter 4 Expansion Slots and Adapter Cards
• An expansion slot is a socket on the motherboard that can hold an adapter card • An adapter card enhances functions of a component of the system unit and/or provides connections to peripherals – Sound card and video card
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click Video Cards below Chapter 4 Page 169 Discovering Computers Fundamentals, 2010 Edition 26 Figure 4-17 Chapter 4 Expansion Slots and Adapter Cards
• Removable flash memory includes: – Memory cards , USB flash drives , and PC Cards /ExpressCard modules
Pages 169 - 170 Discovering Computers Fundamentals, 2010 Edition 27 Figure 4-19 Chapter 4 Ports and Connectors
A port is the point at which a peripheral attaches to or communicates with a system unit (sometimes referred to as a jack)
A connector joins a cable to a port
Pages 170 - 171 Discovering Computers Fundamentals, 2010 Edition 28 Chapter 4 Ports and Connectors
Page 170 Discovering Computers Fundamentals, 2010 Edition 29 Figure 4-20 Chapter 4 Ports and Connectors
• On a notebook computer, the ports are on the back, front, and/or sides
Pages 170 - 171 Discovering Computers Fundamentals, 2010 Edition 30 Figure 4-21 Chapter 4 Ports and Connectors
• A USB port can connect up to 127 different peripherals together with a single connector – You can attach multiple peripherals using a single USB port with a USB hub
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click USB Ports below Chapter 4 Pages 171 - 172 Discovering Computers Fundamentals, 2010 Edition 31 Figure 4-22 Chapter 4 Ports and Connectors
• Other types of ports include: Firewire Bluetooth SCSI port port port
eSATA port IrDA port MIDI port
Click to view Web Link, click Chapter 4, Click Web Link from left navigation, then click Firewire below Chapter 4 Pages 172 - 173 Discovering Computers Fundamentals, 2010 Edition 32 Chapter 4 Ports and Connectors
• A port replicator is an external device that provides connections to peripherals through ports built into the device • A docking station is an external device that attaches to a mobile computer or device
Page 173 Discovering Computers Fundamentals, 2010 Edition 33 Figure 4-23 Chapter 4 Buses
• A bus allows the various devices both inside and attached to the system unit to communicate with each other – Data bus – Address bus • A computer can have these basic types of buses: – System bus – Backside bus – Expansion bus
Page 174 Discovering Computers Fundamentals, 2010 Edition 34 Figure 4-24 Chapter 4 Bays
• A bay is an opening inside the system unit in which you can install additional equipment – A drive bay typically holds disk drives
Page 175 Discovering Computers Fundamentals, 2010 Edition 35 Figure 4-25 Chapter 4 Power Supply
The power supply converts the wall outlet AC power into DC power
Some external peripherals have an AC adapter , which is an external power supply
Page 175 Discovering Computers Fundamentals, 2010 Edition 36 Chapter 4 Putting It All Together
Home Small Office/ Mobile Intel Core 2 Duo or Intel Home Office Intel Core 2 Extreme or Celeron Dual Core or Intel Core 2 Quad or AMD Turion X2 AMD Sempron Intel Core 2 Extreme or AMD Athlon FX or AMD Athlon X2 Dual-Code Minimum RAM: 2 GB Minimum RAM: 2 GB
Minimum RAM: 4 GB
Page 176 Discovering Computers Fundamentals, 2010 Edition 37 Figure 4-26 Chapter 4 Putting It All Together
Power Enterprise Intel Itanium 2 or AMD Intel Core 2 Quad or Quad Core Opteron or Intel Core 2 Extreme or Intel Quad Core Xeon or AMD Athlon FX or AMD Sun UltraSPARC T2 Athlon X2 Dual-Core
Minimum RAM: 8 GB Minimum RAM: 4 GB
Page 176 Discovering Computers Fundamentals, 2010 Edition 38 Figure 4-26 Chapter 4 Keeping Your Computer or Mobile Device Clean
Clean your computer or mobile device once or twice a year
Turn off and unplug your computer or mobile device before cleaning it
Use compressed air to blow away dust
Use an antistatic wipe to clean the exterior of the case and a cleaning solution and soft cloth to clean the screen
Page 177 Discovering Computers Fundamentals, 2010 Edition 39 Chapter 4 Video: The Leopard with a Time Machine
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Discovering Computers Fundamentals, 2010 Edition 40 Chapter 4 Summary
Sequence of operations How memory stores Components of the that occur when a data, instructions, and system unit computer executes an information instruction
Comparison of various How to clean the personal computer exterior and interior of processors on the a system unit market today
Page 178 Discovering Computers Fundamentals, 2010 Edition 41 Chapter 4 Discovering Computers Fundamentals, 2010 Edition
Living in a Digital World
Chapter 4 Complete