Absolute Beginners Guide to A+ Certification. Covers the Hardware and Operating Systems Exam

2017-07-07 02:10:07

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Use the "Key Terms and Definitions" section of the lab to review terms used in this chapter. Try the "Practice Test" to check your comprehension of the chapter. Tackle the "Lab Exercises" to apply your knowledge.

Key Terms and Definitions

ARMD (ATA removable media device)

General term for removable-media drives that connect to the ATA/IDE interface.

ATA (AT Attachment)

The most common type of IDE interface, and the name for a series of standards for IDE drives.

ATA RAID

A RAID array (usually RAID 0 or RAID 1) created with two or more ATA drives. An SATA RAID array uses SATA drives.

ATAPI (AT Attachment Packet Interface)

The type of ATA/IDE interface used by optical and removable-media drives.

block mode

A BIOS option for ATA/IDE drives that enables multiple-sector reads before an IRQ must be issued; speeds up disk throughput on almost all drives.

buffer underrun

A CD writing error that takes place when the drive runs out of data.

busmaster

A PCI device that can control the system bus directly. Most recent motherboards support ATA/IDE busmastering if the appropriate drivers are installed.

cable select

Cable (such as the 80-wire UDMA-66 cable) and jumper setting that assigns master and slave.

CD-R (recordable CD)

Contents can be added but not erased.

CD-ROM

Read-only optical drive compatible with music and data CDs.

CD-RW (rewritable CD)

Contents can be added, changed, and erased.

changeline support

Feature that enables all 3.5-inch floppy drives (and AT-compatible 5.25-inch drives) to automatically sense disk changes. If line 34 of the floppy interface or cable is damaged, this doesn't work properly.

daisy-chain

Connecting multiple devices to a single port with direct connections between devices. Used by SCSI, IEEE-1394, and parallel interfaces. USB uses a variation of daisy-chaining which uses a hub, but the other interfaces allow devices to be connected directly to each other.

device ID

Unique value for each SCSI device in a daisy-chain.

disk cache

Using memory to speed up disk access.

DSDD (double-sided double-density)

Stores half the capacity of DSHD on 3.5-inch drives.

DSED (double-sided extra-density)

Stores twice the capacity of DSDD on 3.5-inch drives, but is not widely used.

DSHD (double-sided high-density )

The most common media type used by floppy drives.

DVD+R

Recordable DVD compatible with DVD+RW Alliance standards.

DVD+RW

Rewritable DVD compatible with DVD+RW Alliance standards.

DVDR/RW

Drives that support DVD-R/RW and DVD+R/RW media.

DVD-R

Recordable DVD compatible with DVD Forum standards.

DVD-RAM

Rewritable DVD compatible with DVD Forum standards; more durable than DVD-RW, can be double sided, but less compatible than other rewritable DVD standards.

DVD-ROM

Read-only optical drive compatible with video and data DVDs.

DVD-RW

Rewritable DVD compatible with DVD Forum standards.

Enhanced IDE

Marketing term used by some vendors to refer to ATA/IDE drives that meet ATA-2 standards.

Extended INT13h

An extension of the standard INT13h BIOS interface for hard disks that allows hard disks to exceed 8.4GB in size .

external hard drive

Hard disks with an enclosure and (usually) an external power source. Most recent models connect to USB 2.0 or IEEE-1394a ports, but some models connect to SCSI ports.

FAT (File Allocation Table)

A special database of file locations and sizes used by DOS and Windows operating systems.

file system

General term used for the organization and naming of files and partitions on a hard disk. Windows uses two major types of file systems: FAT and NTFS.

formatting

The process of creating sectors and tracks on a magnetic disk to organize it for use.

hard drives

Drives that use one or more rigid platters to store data magnetically.

HD-50

High-density 50-pin interface for SCSI.

HD-68

High-density 68-pin interface for SCSI.

host adapter

Term for any disk interface card used by interfaces that build the actual controller into the drive, such as ATA/IDE or SCSI.

IDE (Integrated Drive Electronics)

A type of hard disk, tape, or removable-media drive in which the controller logic is built into the drive.

IDE channel

ATA/IDE host adapter (each channel can handle two drives).

Jaz drive

Iomega removable-media drive with 1GB and 2GB capacities .

lands

Flat section of the spiral data track on a stamped CD or DVD, or a reflective area of the spiral data track on a burned CD or DVD. Compare to pits .

LBA (Logical Block Addressing)

A method of translating the drive's CHS (cylinder-head-sector) geometry to bypass operating system and BIOS limits.

LD-50

50-pin Centronics interface for SCSI.

LS-120

Original 120MB version of the SuperDisk drive and media.

LS-240

Second-generation 240MB version of the SuperDisk drive and media. LS-240 drives can also format standard 1.44MB floppy disks to hold 32MB of data.

LVD ( low-voltage differential)

A type of SCSI signaling used for all Ultra-class and faster devices.

master

Jumper setting that assigns the drive as the first of two drives on an IDE channel.

Master File Table ( MFT )

The location used to store information about files created on a drive using the NTFS file system.

media-sensing hole

A hole in the jacket of 3.5-inch DSHD, DSED, and SuperDisk media that enables the drive to determine the type of media in use and prevents the wrong type of media from being used.

MultiRead

Standard for reading CD-RW media on a CD-ROM drive.

MultiRead2

Standard for reading CD-RW media on a DVD-ROM drive.

Narrow SCSI

8-bit SCSI interface, requires a 50-pin or 25-pin interface.

NTFS (New Technology File System)

The native file system supported by Windows NT/2000/XP. NTFS supports built-in file compression and access control lists, and stores file locations in the Master File Table (MFT).

optical drive

A drive (CD or DVD based) that uses a laser to read or write data.

Orb drive

Castlewood removable-media drive with 2.2GB and 5.7GB capacities.

Peerless drive

Iomega modular removable-media drive with 10GB and 20GB capacities.

phantom directory

Refers to floppy drives that cannot detect a disk change; indicates that changeline support isn't working. If the user doesn't force the drive to reread the new floppy disk, the computer assumes the new disk has the same FAT as the original disk, and trashes the contents of the new disk.

pits

Raised area in the spiral data track of a pressed CD or DVD or a burned area in the spiral data track of a recordable or rewritable CD or DVD. Pits don't reflect light back to the CD or DVD pickup lens. Compare to lands .

random access

Data access method that locates and reads data in any order. Random access is used by hard disk drives, floppy and removable-media disk drives, and optical drives.

read-only caching

Disk-caching method used by Windows for floppy and removable-media drives; uses memory to cache reads, but disk writes go directly to the drive.

read-write heads

Magnetic heads used to read and write data to any type of magnetic media, including disk and tape.

SCAM (SCSI Configuration AutoMagically)

An automatic SCSI configuration method used by some hard disks and SCSI host adapters.

SCSI (Small Computer System Interface)

A sophisticated drive and device interface that supports up to 7 (narrow) or 15 (wide) devices on a single host adapter channel. Supports drives and other I/O devices.

SE (single-ended)

A type of SCSI signaling used for low-speed devices.

sequential access

Data access method that locates and reads data by reading data in the order of creation. Tape drives use sequential access.

sectors

512-byte areas on a disk; the basic building block of all disk storage structures.

Serial ATA ( SATA )

High-speed version of ATA that uses serial signaling; uses same commands as ATA/IDE but a smaller cable with no master/slave jumpering.

slave

Jumper setting that assigns the drive as the second of two drives on an IDE channel.

SuperDisk

Common name for LS-120 and LS-240 drives and media. All SuperDisk drives can also read and write standard 1.44MB and 720KB 3.5-inch floppy disks.

tape drive

Internal or external backup drive that uses various types of magnetic tape to store data. Size measured in native (uncompressed) and 2:1 compressed capacities.

termination

Device setting or connector used to indicate the end of a SCSI daisy-chain.

tracks

A concentric circle of sectors on a magnetic disk.

Ultra DMA ( UDMA )

A high-speed method of transferring data from ATA/IDE drives to memory, which bypasses the processor.

Universal Disk Format ( UDF )

A drag-and-drop method of recording to rewritable CD and DVD media that emulates floppy disk storage. Media must be formatted to enable UDF access, and a compatible reader must be used on systems with read-only drives to read UDF-written media. Some programs can also perform UDF recording with CD-R or recordable DVD media.

Wide SCSI

16-bit SCSI interface; requires a 68-pin interface.

write-behind caching

Disk-caching method used by Windows for hard disks; uses memory to hold (cache) reads and writes to speed disk access.

write-protect

Prevents media from being erased or changed; might use a mechanical or electronic method.

X-rating

Factor used to express transfer rate of CD or DVD drives. For CDs, multiply X rating by 150Mbps. For DVDs, multiply X rating by 1.385MBps.

Zip drive

Iomega-developed removable-media drive with 100MB, 250MB, and 750MB capacities.

Practice Test

1:	Which of the following is a characteristic of magnetic media? (Choose all that apply) Media is divided up into 512-byte areas called clusters. Sectors are organized into tracks. Windows loads device drivers to enable magnetic drives to emulate optical drives. File allocation tables are used to store data.
2:	Your client needs to retrieve data from a floppy disk marked ED. Which type of drive is compatible with this media? 1.44MB 720KB 1.2MB 2.88MB
3:	You need to install a floppy drive and a hard disk into a recent system. Which of the following is the most accurate description of what steps you perform in the system BIOS? (Choose one) Use auto-detect to configure hard disk and floppy drive type. Choose drive type for both hard disk and floppy drive type. Use auto-detect for hard disk and choose drive type for floppy. Install 32-bit device drivers for both drives.
4:	Your client asks you to install a UDMA-100 drive into a computer that supports UDMA-33. Which of the following procedures should be used to enable the drive to run reliably? (Choose one) Use utility software to configure the drive to run at UDMA-33 speeds. Replace the 80-wire cable with a 40-wire cable. Replace the 40-wire cable with an 80-wire cable. No changes are needed.
5:	Your client wants to install an ATA RAID 1 array with a total size of 120GB. Which of the following drive combinations best matches the client's requirements? (Choose one) Two 60GB drives Four 30GB drives Two 120GB drives One 240GB drive partitioned as two 120GB logical drives
6:	You are installing a new hard disk in a system that has a history of overheating . Which of the following drive interfaces would be the best choice to help improve airflow in the system? (Choose one) ATA/IDE Narrow SCSI Serial ATA Wide SCSI
7:	You need to enable DMA transfers for the ATA/IDE devices in the system, but the system is configured to permit only PIO transfers. Which of the following should be installed? (Choose one) 80-wire cable Busmastering drivers 40-wire cable Serial ATA host adapter
8:	Your client asks you to install a SCSI external tape backup on a workstation. The workstation has a SCSI host adapter with an HD-50 connector, but the tape backup has an LD-50 (Centronics) connector. Which of the following should you do? (Choose one) Install an HD-50toLD-50 cable. Replace the host adapter. Connect a device between the tape backup and workstation that has one HD-50 and one LD-50 connector. Adjust the termination on the tape backup.
9:	You need to install a SCSI drive into a system that has a SCSI host adapter originally bundled with a scanner. Which of the following is most likely to be necessary before you can install the drive? (Choose one) Replace the SCSI host adapter with a model suitable for both types of devices. Check the SCSI host adapter for the cable type supported and order the cable suitable for the drive. Enable the SCAM support. Disable parity checking.
10:	You are testing a drive marked as a DVDR/RW drive. Which of the following types of media can you use for testing? (Choose all that apply) DVD-RAM DVD-R DVD+RW CD-RW
11:	Your client's brand-new ATAPI CD-RW drive isn't recognized by Windows XP as a rewritable drive. An Internet connection is not available. Which procedure is most likely to solve the problem? Install the CD-mastering software package you prefer. Install the CD-mastering software the client prefers. Install the CD-mastering software packaged with the drive. Return the drive to the point of purchase and select a different model.
12:	Your client is trying to create CDs with a 12X write CD-RW drive that lacks buffer-underrun prevention features. The drive is experiencing frequent buffer underruns. Which of the following can be used as a workaround until a newer drive can be installed? Reduce write speed to 8X or less. Use higher-rated media (16X or faster). Disable the simulated-write testing feature. Turn on screensavers.
13:	Your client has a 10GB Peerless drive, but would prefer a 20GB external drive. Which of the following options would best meet your client's needs? Install a 20GB or larger ATA/IDE drive. Install another 10GB Peerless drive. Replace the 10GB cartridge with a 20GB cartridge. Install a 20GB Peerless drive.
14:	Your client wants to purchase a Hi-Speed USB external hard disk with a system that has the following ports: USB 1.1, SCSI, parallel Which of the following procedures would ensure best performance? Install another USB 1.1 port for use exclusively by the drive. Install a USB 2.0 port for use by the drive. Install a Wide SCSI host adapter. Connect the drive directly to the USB 1.1 port on the rear of the system instead of a hub.

Lab Exercises

Required equipment : working system, extra ATA/IDE hard disk and CD-ROM drive with drivers, Internet connection, ESD protection (wrist strap, antistatic mat), tools to open system

Optional equipment : SCSI, USB or IEEE-1394 hard disk or removable-media drive with host adapter (card or integrated), media

BIOS and Hard Disk Detective

Start the system and activate the BIOS setup program. Determine the following:

What floppy drives does your system support?

Does your system support booting from CD-ROM?

Can your system boot from a USB drive?

View the hard disk configuration and record the CHS (cylinder-head-sector) values if listed.

Exit BIOS setup, discarding any changes. Restart the system.

Use system configuration software or the Windows Device Manager to determine the brand and model of the hard disk. Visit the vendor's Web site and determine what utility software and technical documents are available for the drive.

Shut down the system.

Jumper and Cable Investigation

Shut down the system and disconnect the AC power cord.

Take the ESD precautions discussed in Chapter 13

Examine the hard disk. Does it have a label indicating jumper positions ?

Review the rear of the drive. What type of cable does it use? How is the drive jumpered? Is the drive cable also used for another drive?

Check the other ATA/IDE or SCSI drives in the system. How are they configured?

Close the system and reconnect the AC power cord.

Optional Exercises

Install a removable-media drive. Do you need to install a new host adapter first? What speed is the host adapter and drive?

Answers to Practice Test


A1:	Answer B (sectors are organized into tracks) is correct. 512-byte areas are called sectors, not clusters; Windows uses device drivers to enable optical drives to emulate magnetic drives; and file allocation tables record the locations of data on the drive, not the data itself.

A2:	Answer D (2.88MB) is correct; this drive uses DSED media. Many recent system BIOSs support this size drive, but it is seldom installed in systems other than some IBM models.

A3:	Answer C (use auto-detect for hard disk and choose drive type for floppy) is correct. Floppy drives don't support auto-detection, but ATA/IDE hard disks and system BIOSs do.

A4:	Answer A (use utility software to configure the drive to run at UDMA-33 speeds) is correct. Some drives are configured by default to run at their maximum UDMA speed, which could cause data loss on systems that don't support it. The type of cable is irrelevant because the system doesn't support speeds that require an 80-wire cable.

A5:	Answer C (two 120GB drives) is correct. An ATA RAID 1 array uses mirroring (one drive is a duplicate of the other), so the size of the array is the size of one of the drives.

A6:	Answer C (Serial ATA) is correct. Serial ATA's narrow data cable doesn't impede airflow the way the wide parallel cables used by ATA/IDE and SCSI do.

A7:	Answer B (busmastering drivers) is correct. The lack of busmastering drivers is the main reason that a DMA-capable system can't do DMA transfers.

A8:	Answer A (install an HD-50toLD-50 cable) is correct. These connectors use the same signals, but in different form factors. This is a relatively common problem with different generations of SCSI devices.

A9:	Answer A (replace SCSI host adapter with model suitable for both types of devices) is correct. SCSI host adapters bundled with scanners often don't support multiple devices, and lack onboard BIOS and support for the higher speeds required by SCSI hard drives.

A10:	Answers B (DVD-R), C (DVD+RW), and D (CD-RW) are correct. These drives are not compatible with DVD-RAM, but work with all other types of rewritable and recordable DVD and CD media.

A11:	Answer C (install the CD-mastering software packaged with the drive) is correct. The program packaged with the drive supports the drive, and makes Windows XP's lack of support for the drive a nonissue.

A12:	Answer A (reduce write speed to 8x or less) is correct. Slowing down the drive's write speed is one of the major methods for improving CD-writing reliability with older drives. Using higher-rated media won't help, and the other options could actually worsen the likelihood of writing a CD.

A13:	Answer C (replace the 10GB cartridge with a 20GB cartridge) is correct. Peerless is a removable-media drive.

A14:	Answer B (install a USB 2.0 port for use by the drive) is correct. Hi-Speed USB is the same as USB 2.0, which runs at 480Mbps, instead of 12Mbps as USB 1.1 does.