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

2. A+ Guide to Managing and Maintaining your PC, 6e2 Objectives Learn how the organization of data on floppy drives and hard drives is similar Learn about hard drive technologies Learn how a computer communicates with a hard drive Learn how to install a hard drive Learn how to solve hard drive problems

3. A+ Guide to Managing and Maintaining your PC, 6e3 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

4. A+ Guide to Managing and Maintaining your PC, 6e4 Learning from Floppy Drives Floppy drives are a fading 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

5. A+ Guide to Managing and Maintaining your PC, 6e5 How Floppy Drives Work Secondary storage devices are organized physically and logically –Physical storage: how data is physically 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 - The cable is called a floppy connector or a Berg connector –Formatting: marking tracks and sectors on a disk –Magnetic read/write heads read/write binary 1s and 0s –Heads attach to an actuator arm that moves over surface

6. A+ Guide to Managing and Maintaining your PC, 6e6 Figure 8-4 3 1 -inch, high-density floppy disk showing tracks and sectors

7. A+ Guide to Managing and Maintaining your PC, 6e7 Figure 8-5 Inside a floppy disk drive

8. A+ Guide to Managing and Maintaining your PC, 6e8 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

9. A+ Guide to Managing and Maintaining your PC, 6e9 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

10. A+ Guide to Managing and Maintaining your PC, 6e10 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

11. A+ Guide to Managing and Maintaining your PC, 6e11 Figure 8-8 Connect colored edge of cable to pin 1

12. A+ Guide to Managing and Maintaining your PC, 6e12 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

13. A+ Guide to Managing and Maintaining your PC, 6e13 Figure 8-10 Inside a hard drive case

14. A+ Guide to Managing and Maintaining your PC, 6e14 Figure 8-11 A hard drive with two platters

15. A+ Guide to Managing and Maintaining your PC, 6e15 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)

16. A+ Guide to Managing and Maintaining your PC, 6e16 Figure 8-13 Floppy drives and older hard drives use a constant number of sectors per track

17. A+ Guide to Managing and Maintaining your PC, 6e17 Figure 8-14 Zone bit recording can have more sectors per track as the tracks get larger

18. The History of Hard Drive Size ATA-1 permitted a maximum hard drive size of 504 MB - First ATA drives connected using a 40-pin ribbon cable LBA allowed for an increase from the max of 504 MB to 8.4 GB by basically lying to the BIOS about its geometry using advanced sector translation - The BIOS was actually causing the limitation Interrupt (INT) 13 extensions allowed for our next increase - The BIOS was rewritten by Phoenix Technologies and now our maximum size increased to 137 GB ATA-6 has been the most recent push for drive size and by changing the LBA from 24-bit to 48-bit addressing, drive size has increased to 144 petabytes which is approximately 144,000,000 GB A+ Guide to Managing and Maintaining your PC, 6e18

19. A+ Guide to Managing and Maintaining your PC, 6e19 Low-Level Formatting Two formatting levels: –Low-level: marks tracks and sectors –High-level: creates boot sector, file system, root directory Manufacturers currently perform most low-level formats –Using the wrong format program can destroy a drive –If necessary, contact the manufacturer for format program At one time, when a drive started to fail, you’d provide a low- level format and reuse the drive With drives today, you’ll backup the data and replace drive

20. A+ Guide to Managing and Maintaining your PC, 6e20 Drive Capacity for Today’s Drives The OS reports the capacity of hard drives Use Windows Explorer to find the size of your drive and the available memory –Right-click the drive letter –Select Properties on the shortcut menu Calculating total capacity if the drive is broken up into several logical drives –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

21. A+ Guide to Managing and Maintaining your PC, 6e21 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

22. A+ Guide to Managing and Maintaining your PC, 6e22 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

23. A+ Guide to Managing and Maintaining your PC, 6e23 The ATA Interface Standards (continued) Parallel ATA –Allows two connectors for two 40-pin data cables –Ribbon cables can accommodate one or two drives –Look for pin 1 by the colored stripe on the side of the cable –ATA-5 introduced the 80-wire, 40-pin data cable - Still has 40-pin cable, but 40 more wires provide grounding allowing for the cable to handle higher rates of speed 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

24. A+ Guide to Managing and Maintaining your PC, 6e24 Figure 8-16 A PC’s hard drive subsystem using parallel ATA

25. A+ Guide to Managing and Maintaining your PC, 6e25 Figure 8-18 A hard drive subsystem using the new serial ATA data cable

26. A+ Guide to Managing and Maintaining your PC, 6e26 The ATA Interface Standards (continued) DMA (direct memory access) transfer mode –7 modes (0 - 6) bypassing CPU in transfer of data to RAM –DMA is faster than PIO 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

27. A+ Guide to Managing and Maintaining your PC, 6e27 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 –Cable-select allows you to use a special cable-select cable and then you set both drives to cable-select 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

28. A+ Guide to Managing and Maintaining your PC, 6e28 Figure 8-22 A motherboard has two IDE channels; each can support a master and slave drive using a single EIDE cable

29. A+ Guide to Managing and Maintaining your PC, 6e29 Figure 8-25 Rear of a serial ATA drive and a parallel ATA drive

30. A+ Guide to Managing and Maintaining your PC, 6e30 SCSI Technology Small Computer System Interface standards –For system bus to peripheral device communication –Support either 7 or 15 devices –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) - Host adapter is usually assigned 7 or 15 –A physical device can embed multiple logical devices

31. A+ Guide to Managing and Maintaining your PC, 6e31 Figure 8-28 Using a SCSI bus, a SCSI host adapter can support internal and external SCSI devices

32. A+ Guide to Managing and Maintaining your PC, 6e32 SCSI Technology (continued) Terminating resistor –Plugged into last device at the end of the chain –Reduces electrical noise or interference on the cable –Termination is required on the end devices - Some devices are configured to automatically terminate themselves 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

33. A+ Guide to Managing and Maintaining your PC, 6e33 Other Interface Standards USB (Universal Serial Bus) –USB 1.1 (12 Mbps) and USB 2.0 (480 Mbps) accommodate hard drives –Up to 127 devices IEEE 1394 (FireWire) – 1394a = 400 Mbps, 1394b = 800 Mbps – Up to 63 devices –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 –4.8 Gbps –Allows up to 126 devices on a single bus

34. A+ Guide to Managing and Maintaining your PC, 6e34 Figure 8-31 This CrossFire hard drive holds 160GB and uses a 1394a or USB 2.0 connection

35. A+ Guide to Managing and Maintaining your PC, 6e35 How to Select a Hard Drive Hard drive must be compatible with the 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 drive may not supported by BIOS Troubleshooting tasks (if drive is not recognized) –Flash the BIOS –Replace the controller card –Replace the motherboard

36. A+ Guide to Managing and Maintaining your PC, 6e36 Installations Using Legacy BIOS Older hard drive standards that may be encountered –CHS (cylinder, head, sector) mode for drives < 528 MB –Large (ECHS) mode for drives from 504 MB - 8.4 GB –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 card and firmware

37. A+ Guide to Managing and Maintaining your PC, 6e37 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

38. A+ Guide to Managing and Maintaining your PC, 6e38 Figure 8-32 Plan for the location of drives within bays

39. A+ Guide to Managing and Maintaining your PC, 6e39 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

40. A+ Guide to Managing and Maintaining your PC, 6e40 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

41. A+ Guide to Managing and Maintaining your PC, 6e41 Figure 8-41 Connect a power cord to each drive

42. A+ Guide to Managing and Maintaining your PC, 6e42 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

43. A+ Guide to Managing and Maintaining your PC, 6e43 Figure 8-45 Standard CMOS setup

44. A+ Guide to Managing and Maintaining your PC, 6e44 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 than PATA: –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

45. A+ Guide to Managing and Maintaining your PC, 6e45 Figure 8-48 This motherboard has four serial ATA connectors

46. A+ Guide to Managing and Maintaining your PC, 6e46 Figure 8-49 American Megatrends, Inc. CMOS setup screen shows installed drives

47. A+ Guide to Managing and Maintaining your PC, 6e47 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

48. A+ Guide to Managing and Maintaining your PC, 6e48 Figure 8-52 Hard drive installed in a wide bay using a universal bay kit adapter

49. A+ Guide to Managing and Maintaining your PC, 6e49 Troubleshooting Hard Drives Problems occur before and after installation Problems may be hardware or software related Hardware-related problems will be addressed

50. A+ Guide to Managing and Maintaining your PC, 6e50 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

51. A+ Guide to Managing and Maintaining your PC, 6e51 Problems with Hard Drive Installations (continued) Things to check if CMOS setup does not show drive –Is autodetection correctly configured in CMOS setup? –Are the jumpers on the drive set correctly? –Are the power cord and data cable connected?

52. A+ Guide to Managing and Maintaining your PC, 6e52 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

53. A+ Guide to Managing and Maintaining your PC, 6e53 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

54. A+ Guide to Managing and Maintaining your PC, 6e54 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

55. A+ Guide to Managing and Maintaining your PC, 6e55 Summary Current floppy disks are 3 ½ inch, high-density disks Floppy disk format: 80 tracks, each with 8 sectors Hard drive physical organization: cylinders, tracks, sectors Hard drive logical organization: boot record, file allocation tables, and root directory Secondary storage device communicates with system using a standard, such as ATA or SCSI

56. A+ Guide to Managing and Maintaining your PC, 6e56 Summary (continued) Parallel ATA (or EIDE): allows connection of up to 4 devices Serial ATA (SATA): specifies one cable per device SCSI group: allow up to 7 or 15 physical devices and multiple logical devices per physical device Other drive interface standards: USB, FireWire, Fibre Channel Newly installed hard drives are usually automatically detected by BIOS