A+ Guide to Managing and Maintaining your PC, 6e. Chapter 8 Hard Drives

A+ Guide to Managing and Maintaining your PC, 6e Chapter 8 Hard Drives

Introduction Hard drive: most important secondary storage device Hard drive technologies have evolved rapidly Hard drive capacities and speeds have increased Interfaces with the computer have also changed Floppy disk will be presented before hard drives Floppy disk is logically organized like a hard drive Practical applications: Managing problems occurring during drive installation Troubleshooting hard drives after installation A+ Guide to Managing and Maintaining your PC, 6e 2

Learning from Floppy Drives Floppy drives are an obsolescent technology Replacements: CD drives and USB flash memory Good reasons for studying floppy drive technology Developing support skills for legacy applications Building a foundation for hard drive support skill set A+ Guide to Managing and Maintaining your PC, 6e 3

How Floppy Drives Work Main memory is organized logically and physically Secondary storage devices are similarly organized Physical storage: how data is written to media Logical storage: how OS and BIOS view stored data How data is physically stored on a floppy disk Two types of floppy disk: 5 ¼ inch or 3 ½ inch Subsystem: drive, 34-pin cable, connector, power cord Formatting: marking tracks and sectors on a disk Magnetic read/write heads read/write binary 1s and 0s Heads attach to actuator arm that moves over surface A+ Guide to Managing and Maintaining your PC, 6e 4

Figure 8-4 3 1 -inch, high-density floppy disk showing tracks and sectors A+ Guide to Managing and Maintaining your PC, 6e 5

Figure 8-5 Inside a floppy disk drive A+ Guide to Managing and Maintaining your PC, 6e 6

How Floppy Drives Work (continued) How data is logically stored on a floppy disk Floppy drives are always formatted using FAT12 Cluster (file allocation unit): smallest grouping of sectors The BIOS manages the disk as a set of physical sectors OS treats the disk as list of clusters (file allocation table) A 3 ½ inch high density floppy disk has 2880 clusters A cluster contains one sector, which contains 512 bytes Format floppy disk using Format or Windows Explorer Structures and features added to the disk Tracks, sectors, boot record, two FATs, root directory A+ Guide to Managing and Maintaining your PC, 6e 7

Figure 8-6 Clusters, or file allocation units, are managed by the OS in the file allocation table, but BIOS manages these clusters as one or two physical sectors on the disk A+ Guide to Managing and Maintaining your PC, 6e 8

How to Install a Floppy Drive It is more cost-effective to replace than repair a drive A simple seven-step installation procedure: 1. Turn off computer, unplug power cord, remove cover 2. Unplug the power cable to the old floppy drive 3. Unscrew and dismount the drive 4. Slide the new drive into the bay 5. If drive is new, connect data cable to motherboard 6. Connect data cable and power cord to drive 7. Replace the cover, turn on computer, verify status A+ Guide to Managing and Maintaining your PC, 6e 9

Figure 8-8 Connect colored edge of cable to pin 1 A+ Guide to Managing and Maintaining your PC, 6e 10

How Hard Drives Work Components of a hard drive: One, two, or more platters (disks) Spindle to rotate all disks Magnetic coating on disk to store bits of data Read/write head at the top and bottom of each disk Actuator to move read/write head over disk surface Hard drive controller: chip directing read/write head Head (surface) of platter is not the read/write head Physical organization includes a cylinder All tracks that are the same distance from disk center A+ Guide to Managing and Maintaining your PC, 6e 11

Figure 8-10 Inside a hard drive case A+ Guide to Managing and Maintaining your PC, 6e 12

Figure 8-11 A hard drive with two platters A+ Guide to Managing and Maintaining your PC, 6e 13

Tracks and Sectors on the Drive Tracks on older drives held the same amount of data Newer drives use zone bit recording Tracks near center have smallest number sectors/track Number of sectors increase as tracks grow larger Every sector still has 512 bytes Sectors identified with logical block addressing (LBA) A+ Guide to Managing and Maintaining your PC, 6e 14

Figure 8-13 Floppy drives and older hard drives use a constant number of sectors per track A+ Guide to Managing and Maintaining your PC, 6e 15

Figure 8-14 Zone bit recording can have more sectors per track as the tracks get larger A+ Guide to Managing and Maintaining your PC, 6e 16

Low-Level Formatting Two formatting levels: Low-level: mark tracks and sectors High-level: create boot sector, file system, root directory Manufacturer currently perform most low-level formats Using the wrong format program could destroy drive If necessary, contact manufacturer for format program Problem: track and sector markings fade Solution for older drives: perform low-level format Solution for new drive: backup data and replace drive Note: zero-fill utilities do not do low-level formats A+ Guide to Managing and Maintaining your PC, 6e 17

Calculating Drive Capacity on Older Drives Constant number of sectors per track The formula was straightforward: Cylinders x heads x sectors/track x 512 bytes/sector Example: 855 cylinders, 7 heads, 17 sectors/track 855 x 7 x 17 x 512 bytes/sector = 52,093,440 bytes Divide by 1024 twice to convert to 49.68 MB capacity A+ Guide to Managing and Maintaining your PC, 6e 18

Drive Capacity for Today s Drives The OS reports the capacity of hard drives Accessing capacity data using Windows Explorer Right-click the drive letter Select Properties on the shortcut menu Calculating total capacity if drive is fully formatted Record capacity of each logical drive on hard drive Add individual capacities to calculate total capacity Reporting total capacity (regardless of formatting) Windows 2000/XP: use Disk Management Windows 9x: use Fdisk A+ Guide to Managing and Maintaining your PC, 6e 19

Hard Drive Interface Standards Facilitate communication with the computer system Several standards exist: Several ATA standards SCSI USB FireWire (also called 1394) Fibre Channel The various standards will be covered A+ Guide to Managing and Maintaining your PC, 6e 20

The ATA Interface Standards Specify how drives communicate with PC system Drive controller interaction with BIOS, chipset, OS Type of connectors used by the drive The motherboard or expansion cards Developed by Technical Committee T13 Published by ANSI Selection criteria: Fastest standard that the motherboard supports OS, BIOS, and drive firmware must support standard A+ Guide to Managing and Maintaining your PC, 6e 21

Table 8-1 Summary of ATA interface standards for storage devices A+ Guide to Managing and Maintaining your PC, 6e 22

The ATA Interface Standards (continued) Parallel ATA Allows two connectors for two 40-pin data cables Ribbon cables can accommodate one or two drives EIDE (Enhanced Integrated Device Electronics) Pertains to how secondary storage device works Drive follows AT Attachment Packet Interface (ATAPI) Four parallel ATA devices can attach with two cables Serial ATA (SATA) cabling Use a serial data path rather than a parallel data path Types of SATA cabling: internal and external A+ Guide to Managing and Maintaining your PC, 6e 23

Figure 8-16 A PC s hard drive subsystem using parallel ATA A+ Guide to Managing and Maintaining your PC, 6e 24

Figure 8-18 A hard drive subsystem using the new serial ATA data cable A+ Guide to Managing and Maintaining your PC, 6e 25

The ATA Interface Standards (continued) DMA (direct memory access) transfer mode 7 modes (0-6) bypassing CPU in transfer of data PIO (Programmed Input/Output) transfer mode 5 modes (0-4) involving CPU in data transfer Independent device timing Enables two drives to run at different speed ATA/ATAPI-6 (ATA/100) breaks the 137 GB barrier Addressable space is 144 petabytes (1.44 x 10 17 PB) Must have support of board, BIOS, OS, IDE controller A+ Guide to Managing and Maintaining your PC, 6e 26

Figure 8-21 The 137-GB barrier existed because of the size of the numbers used to address a sector A+ Guide to Managing and Maintaining your PC, 6e 27

The ATA Interface Standards (continued) Configuring parallel ATA drives Each of two IDE connectors supports an IDE channel Primary/secondary channels each support two devices EIDE devices: hard drive, DVD, CD and Zip drives Devices in each channel configured as master/slave Designate master/slave: jumpers, DIP switches, cable Configuring serial ATA drives One ATA cable supports one drive (no master/slave) Use an ATA controller card in two circumstances: IDE connector not functioning or standard not supported A+ Guide to Managing and Maintaining your PC, 6e 28

Figure 8-22 A motherboard has two IDE channels; each can support a master and slave drive using a single EIDE cable A+ Guide to Managing and Maintaining your PC, 6e 29

Figure 8-25 Rear of a serial ATA drive and a parallel ATA drive A+ Guide to Managing and Maintaining your PC, 6e 30

SCSI Technology Small Computer System Interface standards For system bus to peripheral device communication Support either 7 or 15 devices (depends on standard) Provide for better performance than ATA standards The SCSI subsystem SCSI controller types: embedded or host adapter Host adapter supports internal and external devices Daisy chain: combination of host adapter and devices Each device on bus assigned SCSI ID (0-15) A physical device can embed multiple logical devices A+ Guide to Managing and Maintaining your PC, 6e 31

Figure 8-28 Using a SCSI bus, a SCSI host adapter can support internal and external SCSI devices A+ Guide to Managing and Maintaining your PC, 6e 32

SCSI Technology (continued) Terminating resistor Plugged into last device at the end of the chain Reduces electrical noise or interference on the cable Various SCSI standards SCSI are SCSI-1, SCSI-2, and SCSI-3 Also known as regular SCSI, Fast SCSI, Ultra SCSI Serial attached SCSI (SAS): compatible with serial ATA Ensure all components of subsystem use one standard A+ Guide to Managing and Maintaining your PC, 6e 33

Other Interface Standards USB (Universal Serial Bus) USB 1.1 and USB 2.0 accommodate hard drives A USB device connects to a PC via a USB port IEEE 1394 (FireWire) Uses serial transmission of data Device can connect to PC via FireWire external port Device also attaches to an internal connector Fibre Channel Rival to SCSI Allows up to 126 devices on a single bus A+ Guide to Managing and Maintaining your PC, 6e 34

Figure 8-31 This CrossFire hard drive holds 160GB and uses a 1394a or USB 2.0 connection A+ Guide to Managing and Maintaining your PC, 6e 35

How to Select a Hard Drive Hard drive must match OS and motherboard BIOS uses autodetection to prepare the device Drive capacity and configuration are selected Best possible ATA standard is part of configuration Selected device may not supported by BIOS Troubleshooting tasks (if device is not recognized) Flash the BIOS Replace the controller card Replace the motherboard A+ Guide to Managing and Maintaining your PC, 6e 36

Installations Using Legacy BIOS Older hard drive standards that may be encountered CHS (cylinder, head, track) mode for drives < 528 MB Large (ECHS) mode for drives from 504 MB - 8.4 GB The 33.8 GB limitation or the 137 GB limitation How to install a drive not supported by BIOS Let the BIOS see the drive as a smaller drive Upgrade the BIOS Replace the motherboard Use a software interface between BIOS and drive Substitute BIOS with ATA connector and firmware A+ Guide to Managing and Maintaining your PC, 6e 37

Steps to Install a Parallel ATA Drive Components needed: The drive itself 80-conductor or 40-conductor data cable Kit to make drive fit into much larger bay (optional) Adapter card (if board does not have IDE connection) Steps for installing parallel ATA drive: Step 1: Prepare for the installation Know your starting point Read the documentation Plan the drive configuration Prepare your work area and take precautions A+ Guide to Managing and Maintaining your PC, 6e 38

Figure 8-32 Plan for the location of drives within bays A+ Guide to Managing and Maintaining your PC, 6e 39

Steps to Install a Parallel ATA Drive (continued) Steps for installing parallel ATA drive (continued): Step 2: Set the jumpers or DIP switches Step 3: Mount the drive in the drive bay Remove the bay for the hard drive Securely mount the drive in the bay Connect the data cables to the drives (can be done later) Re-insert (and secure) the bay in the case Install a power connection to each drive Connect the data cable to the IDE connector on board Attach bay cover and other connections (if needed) Verify BIOS recognizes device before adding cover A+ Guide to Managing and Maintaining your PC, 6e 40

Figure 8-33 A parallel ATA drive most likely will have diagrams of jumper settings for master and slave options printed on the drive housing A+ Guide to Managing and Maintaining your PC, 6e 41

Figure 8-41 Connect a power cord to each drive A+ Guide to Managing and Maintaining your PC, 6e 42

Steps to Install a Parallel ATA Drive (continued) Steps for installing parallel ATA drive (continued): Step 4: Use CMOS setup to verify hard drive settings Step 5: Partition and format the drive If installing an OS, boot from Windows setup CD If not, use Disk Management utility or Fdisk and Format A+ Guide to Managing and Maintaining your PC, 6e 43

Figure 8-45 Standard CMOS setup A+ Guide to Managing and Maintaining your PC, 6e 44

Serial ATA Hard Drive Installations No jumpers to set on the drive Each serial ATA connector is dedicated to 1 drive A simpler installation process: Install the drive in the bay (like parallel ATA drive) Connect a power cord to the drive Documentation identifies which connector to use Example: use red connectors (SATA1, SATA2) first After checking connections, verify drive is recognized A+ Guide to Managing and Maintaining your PC, 6e 45

Figure 8-48 This motherboard has four serial ATA connectors A+ Guide to Managing and Maintaining your PC, 6e 46

Figure 8-49 American Megatrends, Inc. CMOS setup screen shows installed drives A+ Guide to Managing and Maintaining your PC, 6e 47

Installing a Hard Drive in a Wide Bay Universal bay kit: adapts a drive to a wide bay Adapter spans distance between drive and bay A+ Guide to Managing and Maintaining your PC, 6e 48

Figure 8-52 Hard drive installed in a wide bay using a universal bay kit adapter A+ Guide to Managing and Maintaining your PC, 6e 49

Troubleshooting Hard Drives Problems occur before and after installation Problems may be hardware or software related Hardware-related problems will be addressed A+ Guide to Managing and Maintaining your PC, 6e 50

Problems with Hard Drive Installations CMOS setup does not reflect new hard drive Solution: Enable autodetection and reboot system Error message: Hard drive not found. Reseat the data cable and reboot the PC Error message: No boot device available. Insert bootable disk and restart the machine Error message 601 appears on the screen Connect the power cord to the floppy disk drive Error message: Hard drive not present Restore jumpers to their original state A+ Guide to Managing and Maintaining your PC, 6e 51

Problems with Hard Drive Installations (continued) Things to check if CMOS setup does not show drive Does your system BIOS recognize large drives? Is autodetection correctly configured in CMOS setup? Are the jumpers on the drive set correctly? Are the power cord and data cable connected? A+ Guide to Managing and Maintaining your PC, 6e 52

How to Approach a Hard Drive Problem After the Installation Some post-installation problems Corrupted data files A corrupted Windows installation A hardware issue preventing system from booting Preparation steps Start with the end user: conduct an interview Prioritize what you have learned Example: make data backup your first priority Be aware of available resources Examples: documentation, Internet, Technical Support A+ Guide to Managing and Maintaining your PC, 6e 53

Hard Drive Hardware Problems Causes of problems present during boot: Hard drive subsystem Partition table File system on the drive Files required for the OS to boot Some things to do if POST reveals problem Check the jumper settings on the drive Check the cable for frayed edges or other damage Try booting from another media; e.g. setup CD Check manufacturer Web site for diagnostic software A+ Guide to Managing and Maintaining your PC, 6e 54

Hard Drive Hardware Problems (continued) Bumps are bad A scratched surface may cause a hard drive crash Data may be recovered, even if drive is inaccessible Invalid drive or drive specification System BIOS cannot read partition table information Boot from recovery CD and check partition table To be covered in later chapters Bad sector errors Problem due to fading tracks and sectors Solution: replace the drive A+ Guide to Managing and Maintaining your PC, 6e 55

Troubleshooting Floppy Drives and Disks Table 8-4 has two columns One identifies errors occurring before and after boot Another displays troubleshooting tasks A+ Guide to Managing and Maintaining your PC, 6e 56

Table 8-4 Floppy drive and floppy disk errors that can occur during and after the boot A+ Guide to Managing and Maintaining your PC, 6e 57

Table 8-4 Floppy drive and floppy disk errors that can occur during and after the boot (continued) A+ Guide to Managing and Maintaining your PC, 6e 58