Understanding Memory
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Transcript of Understanding Memory
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Understanding Memory
• http://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Eprom.jpg/800px-Eprom.jpg
Discovering Computers 2012: Chapter2- 4
Memory
• Bytes and Addressable memory• Memory Sizes• Types of Memory• RAM• Cache• ROM• Flash Memory• CMOS• Memory Access Time
Discovering Computers 2012: Chapter 2-4 3
Objective Overview
Differentiate among the various types of
memory
See Page 209 for Detailed Objectives
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:
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The operating system and other system software
Application programs
Data being processed and the
resulting information
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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 223 Figure 4-17
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Memory
• The system unit contains two types of memory:
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Volatile memory
Loses its contents when power is turned off
Example includes RAM
Nonvolatile memory
Does not lose contents when power is removed
Examples include ROM, flash memory, and CMOS
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Memory
Page 224 Figure 4-18
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Memory
• Three basic types of RAM chips exist:
Page 225 Figure 4-19
Dynamic RAM (DRAM) Static RAM (SRAM) Magnetoresistive
RAM (MRAM)
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Memory
• RAM chips usually reside on a memory module and are inserted into memory slots
Page 225 Figure 4-20
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Memory
• The amount of RAM necessary in a computer often depends on the types of software you plan to use
Page 226 Figure 4-21
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Memory
• Memory cache speeds the processes of the computer because it stores frequently used instructions and data
Page 227 Figure 4-22
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Memory
Read-only memory (ROM) refers to memory chips storing permanent data and instructions
• Firmware
A PROM (programmable read-only memory) chip is a blank ROM chip that can be written to permanently
• EEPROM can be erased
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Memory
• Flash memory can be erased electronically and rewritten– CMOS technology provides high speeds and consumes
little power
Pages 228 – 229Figure 4-23
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Memory
• Access time is the amount of time it takes the processor to read from memory– Measured in nanoseconds
Page 229 Figures 4-24 – 4-25
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Putting It All Together
HomeIntel Core i5 or
Intel Core 2 i3 or AMD Athlon II orAMD Sempron
Minimum RAM: 2 GB
Small Office/Home Office
Intel Core i7 or Intel Core i7 Extreme or AMD Phenom II or
AMD Athlon II
Minimum RAM: 4 GB
MobileIntel Core i7 Extreme
or Intel Core i7 or
AMD Phenom II or AMD Turion II
Minimum RAM: 2 GB
Page 239 Figure 4-38
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Putting It All Together
PowerIntel Xeon or
Intel Itanium orAMD Opteron
Minimum RAM: 8 GB
EnterpriseIntel Core i7 or
Intel Core i7 Extreme or AMD Phenom II or
AMD Athlon II
Minimum RAM: 4 GB
Page 239 Figure 4-38
Discovering Computers 2012: Chapter 4 17
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
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Video: The Leopard with a Time Machine
CLICK TO START
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Summary
Differentiate among the various types of
memory
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Chapter 2
Chapter 2Complete