Memory and Floppy Drives

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Chapter 6

• Memory and Floppy Drives

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You Will Learn

• About the different kinds of physical memory and
  how they work
  
• How to upgrade and troubleshoot memory
• How floppy drives work and how to support them

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Physical Memory

• ROM
• RAM
• Static RAM (SRAM)
• Dynamic RAM (DRAM)

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Dynamic RAM
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ROM on the Motherboard
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ROM on the Motherboard

• ROM chips (firmware)
• EPROM
• EEPROM (flash ROM chips)

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RAM on the Motherboard
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Static RAM Technologies

• Synchronous SRAM
• Burst SRAM
• Pipelined burst SRAM
• Asynchronous SRAM

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How SRAM Is Used in Different Memory Caches
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How Memory Caching Works
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SRAM on the Motherboard
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Dynamic RAM Technologies

• SIMMs (single inline memory modules)
• DIMMs (dual inline memory modules)
• RIMM modules (inline memory modules manufactured
  by Rambus, Inc.)

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DRAM Technologies
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DIMMs
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RIMMs
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Comparison of Data Throughput of Memory
Technologies
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Parity and Error Checking
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Upgrading Memory

• What to look for when buying memory chips and
  modules
  
• How much and what kind of memory to buy

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What to Look for When Buying Memory Chips and
Modules

• Use fastest memory motherboard can support
• Match tin leads to tin connectors and gold leads
  to gold connectors
  
• Date stamps on remanufactured and used modules
  should be relatively close together
  
• Beware re-marked chips

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How Much and What Kind of Memory to Buy

• Use type, size, density, and speed of memory the
  motherboard supports
  
• Match memory modules already installed

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How Much and What Kind of Memory to Buy
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Installing Memory SIMM
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Installing Memory DIMM
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Installing Memory DIMM
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Troubleshooting Memory

• Computer does not recognize new SIMMs, DIMMs, or
  RIMMs, or memory error messages appear
  
• Memory errors occur during normal operation, and
  you have not just upgraded memory

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Floppy Drives

• How data is storedphysically and logically
• How to manage the data
• How to install a floppy disk drive on a PC

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Physical Data Storage on a Floppy Disk

• Disk must be formatted process of marking
  tracks and sectors to prepare disk to receive data

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Floppy Drive Subsystem
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Tracks and Sectors
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Inside a Floppy Disk Drive
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Track Widths
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Logical Data Storage on a Floppy
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Formatting Process for a Floppy

• Create tracks and sectors
• Create boot record
• Create two copies of file allocation table (FAT)
• Create root directory

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Contents of Floppy DiskBoot Record
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The Root Directory Table
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The Root Directory Table
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Using Commands to Manage a Floppy Disk

• Format Drive /S /VVolumename /Q /U /Autotest
• Used to format floppy disks and logical drives
• /S option makes a drive bootable
• Chkdsk drive /F /V
• Checks drives for errors and repairs them

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Using Windows to Manage a Floppy Disk
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Replacing a Floppy Drive

• Check that computer and other peripherals are
  working
  
• Turn off computer and remove cover (Figure 6-20)
• Unplug data cable and power cable from old drive
  unscrew and dismount drive (Figure 6-21)
  
• Slide new drive into bay reconnect data cable
  and power cable (Figure 6-22)
  
• Turn computer on check setup test drive

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Replacing a Floppy Drive
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Replacing a Floppy Drive
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Replacing a Floppy Drive
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When a Floppy Disk Drive Doesnt Work

• Check physical condition of disk
• Check error messages
• Error messages in the 600 range occur when a
  floppy drive does not pass the POST test
  
• Check CMOS settings
• Check cables connected to drive

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Common Error Messages and Their Meanings

• Non-system disk or disk error. Replace and strike
  any key when ready.
  
• Invalid or missing COMMAND.COM
• Incorrect DOS version
• Invalid Drive Specification
• Not ready reading drive A, Abort, Retry, Fail?

continued
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Common Error Messages and Their Meanings

• General failure reading drive A, Abort, Retry,
  Fail?
  
• Track 0 bad, disk not usable
• Write-protect error writing drive A

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Chapter Summary

• Physical memory
• ROM on the motherboard
• RAM on the motherboard
• Static RAM (SRAM)
• Dynamic RAM (DRAM)
• Upgrading, installing, and troubleshooting memory

continued
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Chapter Summary

• Floppy drives
• How data is physically and logically stored on a
  floppy disk
  
• Formatting process
• Managing a floppy disk with commands or Windows
• Exchanging, supporting, and replacing, or adding
  floppy drives
  
• Troubleshooting floppy drives