A
Abbreviation for ampere(s).
AC
Abbreviation for alternating current.
adapter card
An expansion card that plugs into an
expansion-card connector on the computer's system board. An adapter card adds some
specialized function to the computer by providing an interface between the expansion bus
and a peripheral device. Examples of adapter cards include network cards, sound boards,
and SCSI adapters.
ADC
Abbreviation for analog-to-digital
converter.
ADI
Abbreviation for Autodesk Device
Interface.
AI
Abbreviation for artificial
intelligence.
ANSI
Acronym for American National Standards
Institute.
application program
Software designed to help you perform a
specific task, such as a spreadsheet or word processor. Application programs are distinct
from operating system and utility software.
ASCII
Acronym for American Standard Code for
Information Interchange. A text file containing only characters from the ASCII character
set (usually created with a text editor, such as MS-DOS Editor or Notepad in Windows), is
called an ASCII file.
ASIC
Acronym for application-specific
integrated circuit.
ASPI
Advanced SCSI programming interface.
autoexec.bat
file
When you boot your computer, MS-DOS runs
any commands contained in the text file, autoexec.bat (after running
any commands in the config.sys file). An autoexec.bat
file is not required to boot MS-DOS, but provides a convenient place to run commands that
are essential for setting up a consistent computing environment--such as loading mouse or
network software.
backup
A copy of a program or data file. As a
precaution, you should back up your computer's hard-disk drive on a regular basis. Before
making a change to the configuration of your computer, you should back up important
start-up files, such as autoexec.bat and config.sys for
MS-DOS or win.ini and system.ini for Windows.
base memory
Synonym for conventional memory. See
also conventional memory.
BASIC
Acronym for Beginner's All-Purpose
Symbolic Instruction Code, a programming language. MS-DOS includes a version of BASIC.
batch file
An ASCII text file containing a list of
commands that run in sequence. Batch files must have a filename extension of bat.
baud rate
Data transmission speed. For example,
modems are designed to transmit data at one or more specified baud rate(s) through the COM
(serial) port of a computer.
BBS
Abbreviation for bulletin board service.
A computer system that serves as a central location for accessing data or relaying
messages by modem. For example, Dell's TechConnect BBS contains the latest version of
software such as video drivers and the Dell Directory. If your system has a modem, you can
access the BBS and download the most recent version of this software.
beep code
A diagnostic system message in the form
of a series of beeps from your computer's speaker. Refer to your Diagnostics and
Troubleshooting Guide for a complete discussion of system beep codes.
BIOS
Acronym for basic input/output system.
Your computer's BIOS contains programs stored on a ROM chip. The BIOS controls the
following:
- Communications between the microprocessor and peripheral devices,
such as the keyboard and the video adapter
- Miscellaneous functions, such as system messages
bit
The smallest unit of information
interpreted by your computer.
boot routine
When you start your computer, it clears
all memory, initializes devices, and loads the operating system. Unless the operating
system fails to respond, you can reboot (also called warm boot) your computer by pressing
<Ctrl><Alt><Del>; otherwise, you must perform a cold boot by pressing
the reset button (if your computer has one) or by turning the computer off, then back on.
bootable diskette
You can start your computer from a
diskette in drive A. To make a bootable diskette, insert a diskette in drive A, type sys
a: at the command line prompt, then press <Enter>. Use this bootable diskette if
your computer will not boot from the hard-disk drive.
bpi
Abbreviation for bits per inch.
bps
Abbreviation for bits per second.
BTU
Abbreviation for British thermal unit.
bus
A bus forms an information pathway
between the components of a computer. Your computer contains an expansion bus that allows
the microprocessor to communicate with controllers for all the various peripheral devices
connected to the computer. Your computer also contains an address bus and a data bus for
communications between the microprocessor and RAM.
byte
Eight contiguous bits of information,
the basic data unit used by your computer.
BZT
Abbreviation for Bundesamt fur
Zulassungen in der Telekommunikation.
C
Abbreviation for Celsius.
cache
To facilitate quicker data retrieval, a
storage area for keeping a copy of data or instructions. For example, your computer's BIOS
may cache ROM code in faster RAM. Or, a disk-cache utility may reserve RAM in which to
store frequently accessed information from your computer's disk drives; when a program
makes a request to a disk drive for data that is in the cache, the disk-cache utility can
retrieve the data from RAM faster than from the disk drive.
card-edge connector
On the bottom of an expansion card, the
metal-contact section that plugs into an expansion-card connector.
CCFT
Abbreviation for cold cathode
fluorescent tube.
CD-ROM
Abbreviation for compact disc read-only
memory. CD-ROM drives use optical technology to read data from compact discs. Compact
discs are read-only storage devices; you cannot write new data to a compact disc with
standard CD-ROM drives.
CGA
Abbreviation for color graphics adapter.
cm
Abbreviation for centimeter(s).
CMOS
Acronym for complementary metal-oxide
semiconductor. In computers, CMOS memory chips are often used for NVRAM storage.
COM n
The MS-DOS device names for the first
through fourth serial ports on your computer are COM1, COM2, COM3, and COM4. MS-DOS
supports up to four serial ports. However, the default interrupt for COM1 and COM3 is
IRQ4, and the default interrupt for COM2 and COM4 is IRQ3. Therefore, you must be careful
when configuring software that runs a serial device so that you don't create an interrupt
conflict.
CON
The MS-DOS device name for the console,
which includes your computer's keyboard and text displayed on the screen.
config.sys
file
When you boot your computer, MS-DOS runs
any commands contained in the text file, config.sys (before running any
commands in the autoexec.bat file). A config.sys file
is not required to boot MS-DOS, but provides a convenient place to run commands that are
essential for setting up a consistent computing environment--such as loading device
drivers with a device= statement.
controller
A chip or expansion card that controls
the transfer of data between the microprocessor and a peripheral, such as a disk drive
or the keyboard.
conventional memory
The first 640 KB of RAM. Unless they are
specially designed, MS-DOS programs are limited to running in conventional memory. See
also EMM, expanded memory, extended memory, HMA, memory manager, upper memory area, and
XMM.
coprocessor
A coprocessor relieves the computer's
microprocessor of specific processing tasks. A math coprocessor, for example, handles
numeric processing. A graphics coprocessor handles video rendering. The Intel ®
Pentium ® microprocessor includes a built-in math coprocessor.
cpi
Abbreviation for characters per inch.
CPU
Abbreviation for central processing
unit. See also microprocessor.
cursor
In character-based MS-DOS programs, the
cursor is usually a block or an underscore (possibly blinking) that represents the
position at which the next character typed will appear. Windows programs can design their
own cursors--common cursor symbols include the pointer arrow and the text-insertion
I-beam.
DAC
Acronym for digital-to-analog converter.
DAT
Acronym for digital audio tape.
dB
Abbreviation for decibel(s).
dBA
Abbreviation for adjusted decibel(s).
DC
Abbreviation for direct current.
device driver
A device driver allows the operating
system or a program to interface correctly with a peripheral, such as a printer or network
card. Some device drivers--such as network drivers--must be loaded from the config.sys
file (with a device= statement) or as memory-resident programs (usually, from the autoexec.bat
file). Others--such as video drivers--must load when you start the program for which they
were designed.
diagnostics
See diskette-based diagnostics.
DIMM
Acronym for dual in-line memory module.
DIN
Acronym for Deutsche Industrie Norm.
DIP
Acronym for dual in-line package. A
circuit board, such as a system board or expansion card, may contain DIP switches for
configuring the circuit board. DIP switches are always toggle switches, with an ON
position and an OFF position.
directory
Directories help keep related files
organized on a disk in a hierarchical, "inverted tree" structure. Each disk has
a "root" directory; for example, a c:\> prompt normally
indicates that you are at the root directory of hard-disk drive C. Additional directories
that branch off of the root directory are called subdirectories. Subdirectories may
contain additional directories branching off of them.
diskette-based
diagnostics
A comprehensive set of diagnostic tests
for your Dell computer. To use the diskette-based diagnostics, you must boot your computer
from the Dell Diagnostics Diskette. Refer to your Installation and Troubleshooting Guide
for a complete discussion about how to use the diskette-based diagnostics.
display adapter
See video adapter.
DMA
Abbreviation for direct memory access. A
DMA channel allows certain types of data transfer between RAM and a device to bypass the
microprocessor.
DOC
Abbreviation for Department of
Communications (in Canada).
dpi
Abbreviation for dots per inch.
DPMS
Abbreviation for Display Power
Management Signaling. A standard developed by the Video Electronics Standards Association
that defines the hardware signals sent by a video controller to activate power management
states in a video display or monitor. A monitor is said to be DPMS-compliant when it is
designed to enter a power management state after receiving the appropriate signal from a
computer's video controller.
DRAM
Abbreviation for dynamic random-access
memory. A computer's RAM is usually made up entirely of DRAM chips. Because DRAM chips
cannot store an electrical charge indefinitely, your computer continually refreshes each
DRAM chip in the computer.
drive-type number
Your computer can recognize a number of
specific hard-disk drives. Each is assigned a drive-type number that is stored in NVRAM.
The hard-disk drive(s) specified in your computer's System Setup program must match the
actual drive(s) installed in the computer. The System Setup program also allows you to
specify physical parameters (cylinders, heads, write precomp, landing zone, and capacity)
for drives not included in the table of drive types stored in NVRAM.
DS/DD
Abbreviation for
double-sided/double-density.
DS/HD
Abbreviation for
double-sided/high-density.
DTE
Abbreviation for data terminal
equipment. Any device (such as a computer system) that can send data in digital form by
means of a cable or communications line. The DTE is connected to the cable or
communications line through a data communications equipment (DCE) device, such as a modem.
ECC
Abbreviation for error correction code.
ECP
Abbreviation for Extended Capabilities
Port.
EDO
Abbreviation for extended-data output. A
type of RAM chip that holds data on the chip's output data lines for a longer period of
time than fast-page mode RAM chips. The EDO RAM chips are also faster than fast-page mode
RAM chips.
EEPROM
Acronym for electrically erasable
programmable read-only memory.
EGA
Abbreviation for enhanced graphics
adapter.
EISA
Acronym for Extended Industry-Standard
Architecture, a 32-bit expansion-bus design. The expansion-card connectors in an EISA
computer are also compatible with 8- or 16-bit ISA expansion cards.
To avoid a configuration conflict when
installing an EISA expansion card, you must use the EISA Configuration Utility. This
utility allows you to specify which expansion slot contains the card and obtains
information about the card's required system resources from a corresponding EISA
configuration file.
EMC
Abbreviation for Electromagnetic
Compatibility.
EMI
Abbreviation for electromagnetic
interference.
EMM
Abbreviation for expanded memory
manager. A software utility that uses extended memory to emulate expanded memory on
computers with an Intel386 or higher microprocessor. See also conventional
memory, expanded memory, extended memory, memory manager, and XMM.
EMS
Abbreviation for Expanded Memory
Specification. See also expanded memory, memory manager, and XMS.
EPROM
Acronym for erasable programmable
read-only memory.
ESD
Abbreviation for electrostatic
discharge. Refer to "Safety Instructions" at the front of your User's Guide for
a complete discussion of ESD.
ESDI
Acronym for enhanced small-device
interface.
expanded memory
A technique for accessing RAM above
1 MB. To enable expanded memory on your computer, you must use an EMM. You should
configure your system to support expanded memory only if you run application programs that
can use (or require) expanded memory. See also conventional memory, EMM, extended memory,
and memory manager.
expansion bus
Your computer contains an expansion bus
that allows the microprocessor to communicate with controllers for peripheral devices,
such as a network card or an internal modem.
expansion-card connector
A connector on the computer's system
board for plugging in an expansion card.
extended memory
RAM above 1 MB. Most software that can
use it, such as Windows, requires that extended memory be under the control of an XMM. See
also conventional memory, expanded memory, memory manager, and XMM.
external cache memory
A RAM cache using SRAM chips. Because
SRAM chips operate at several times the speed of DRAM chips, the microprocessor can
retrieve data and instructions faster from external cache memory than from RAM.
F
Abbreviation for Fahrenheit.
FAT
Acronym for file allocation table. The
file system structure used by MS-DOS to organize and keep track of file storage. The
Microsoft Windows NT ® operating system can optionally use a FAT file system
structure.
FCC
Abbreviation for Federal Communications
Commission.
flash memory
A type of EEPROM chip that can be
reprogrammed from a utility on diskette while still installed in a computer; most EEPROM
chips can only be rewritten with special programming equipment.
format
To prepare a hard-disk drive or diskette
for storing files. An unconditional format deletes all data stored on the disk. The format
command in MS-DOS 5.0 or higher includes an option that allows you to unformat a disk, if
you have not yet used the disk for file storage.
ft
Abbreviation for feet.
g
Abbreviation for gram(s).
G
Abbreviation for gravities.
GB
Abbreviation for gigabyte(s). A gigabyte
equals 1,024 megabytes or 1,073,741,824 bytes.
graphics coprocessor
See coprocessor.
graphics mode
See video mode.
GUI
Acronym for graphical user interface.
h
Abbreviation for hexadecimal. A base-16
numbering system, often used in programming to identify addresses in the computer's RAM
and I/O memory addresses for devices. The sequence of decimal numbers from 0 through 16,
for example, is expressed in hexadecimal notation as: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B,
C, D, E, F, 10. In text, hexadecimal numbers are often followed by h or preceded by 0x.
MS-DOS conventional memory--the first 640 KB of memory addresses--is from 00000h to
9FFFFh; the MS-DOS upper memory area--memory addresses between 640 KB and 1 MB--is from
A0000h to FFFFFh.
heat sink
A metal plate with metal pegs or ribs
that help dissipate heat. Some microprocessors include a heat sink.
HMA
Abbreviation for high memory area. The
first 64 KB of extended memory above 1 MB. A memory manager that conforms to the XMS
can make the HMA a direct extension of conventional memory. See also conventional memory,
memory manager, upper memory area, and XMM.
host adapter
A host adapter implements communication
between the computer's bus and the controller for a peripheral. (Hard-disk drive
controller subsystems include integrated host adapter circuitry.) To add a SCSI expansion
bus to your system, you must install the appropriate host adapter.
HPFS
Abbreviation for the High Performance
File System option in the Windows NT operating system.
Hz
Abbreviation for hertz.
I/O
Abbreviation for input/output. The
keyboard and a printer, for example, are I/O devices. In general, I/O activity can be
differentiated from computational activity. For example, when a program sends a document
to the printer, it is engaging in I/O activity; when the program sorts a list of terms, it
is engaging in computational activity.
ID
Abbreviation for identification.
interlacing
A technique for increasing video
resolution by only updating alternate horizontal lines on the screen. Because interlacing
can result in noticeable screen flicker, most users prefer noninterlaced video adapter
resolutions.
internal microprocessor
cache
An instruction and data cache built in
to the microprocessor. The Pentium microprocessor, for example, includes a 16-KB internal
cache, which is set up as an 8-KB read-only instruction cache and an 8-KB read/write data
cache.
IPX
Acronym for internetwork packet
exchange.
IRQ
Abbreviation for interrupt request. A
signal that data is about to be sent to or received by a peripheral travels by an IRQ line
to the microprocessor. Each peripheral connection must be assigned an IRQ number. For
example, the first serial port in your computer (COM1) is assigned to IRQ4 by default. Two
devices can share the same IRQ assignment, but you cannot operate both devices
simultaneously.
ISA
Acronym for Industry-Standard
Architecture. A 16-bit expansion bus design. The expansion-card connectors in an ISA
computer are also compatible with 8-bit ISA expansion cards.
ITE
Abbreviation for information technology
equipment.
JEIDA
Acronym for Japanese Electronic Industry
Development Association.
K
Abbreviation for kilo-, indicating
1,000.
KB
Abbreviation for kilobyte(s), 1,024
bytes.
KB/sec
Abbreviation for kilobyte(s) per second.
Kbit(s)
Abbreviation for kilobit(s), 1,024 bits.
Kbit(s)/sec
Abbreviation for kilobit(s) per second.
key combination
A command requiring that you press
multiple keys at the same time. For example, you can reboot your computer by pressing the
<Ctrl><Alt><Del> key combination.
kg
Abbreviation for kilogram(s), 1,000
grams.
kHz
Abbreviation for kilohertz, 1,000 hertz.
|
LAN
Acronym for local area network. A LAN
system is usually confined to the same building or a few nearby buildings, with all
equipment linked by wiring dedicated specifically to the LAN.
lb
Abbreviation for pound(s).
LCD
Abbreviation for liquid crystal display.
A low-power display often used for notebook computers. An LCD consists of a liquid crystal
solution between two sheets of polarizing material. An electric current causes each
crystal to act like a shutter that can open to allow light past or close to block the
light.
LED
Abbreviation for light-emitting diode.
An electronic device that lights up when a current is passed through it.
LIF
Acronym for low insertion force. Some
computers use LIF sockets and connectors to allow devices such as the microprocessor chip
to be installed or removed with minimal stress to the device.
LIM
Acronym for Lotus/Intel/Microsoft. LIM
usually refers to version 4.0 of the EMS.
LN
Abbreviation for load number.
local bus
On a computer with local-bus expansion
capability, certain peripheral devices (such as the video adapter circuitry) can be
designed to run much faster than they would with a traditional expansion bus. Some
local-bus designs allow peripherals to run at the same speed and with the same width data
path as the computer's microprocessor.
LPTn
The MS-DOS device names for the first
through third parallel printer ports on your computer are LPT1, LPT2, and LPT3.
LUN
Acronym for logical unit number.
m
Abbreviation for meter(s).
mA
Abbreviation for milliampere(s).
mAh
Abbreviation for milliampere-hour(s).
math coprocessor
See coprocessor.
MB
Abbreviation for megabyte(s). The term
megabyte means 1,048,576 bytes; however, when referring to hard-disk drive storage, the
term is often rounded to mean 1,000,000 bytes.
MBR
Abbreviation for master boot record.
MDA
Abbreviation for monochrome display
adapter.
memory
A computer can contain several different
forms of memory, such as RAM, ROM, and video memory. Frequently, the word memory is used
as a synonym for RAM; for example, an unqualified statement such as "ºa computer
with 8 MB of memory" refers to a computer with 8 MB of RAM.
memory address
A specific location, usually expressed
as a hexadecimal number, in the computer's RAM.
memory manager
A utility that controls the
implementation of memory in addition to conventional memory, such as extended or expanded
memory. See also conventional memory, EMM, expanded memory, extended memory, HMA, upper
memory area, and XMM.
MGA
Abbreviation for monochrome graphics
adapter.
MHz
Abbreviation for megahertz.
microprocessor
Because it is the primary computational
chip inside the computer, it is customary to refer to the microprocessor as "the
computer's brain." The microprocessor contains an arithmetic processing unit and a
control unit. Software written for one microprocessor must usually be revised to run on
another microprocessor. CPU is a synonym for microprocessor.
min
Abbreviation for minute(s).
mm
Abbreviation for millimeter(s).
mouse
A pointing device that controls the
movement of the cursor on a screen. Mouse-aware software allows you to activate commands
by clicking a mouse button while pointing at objects displayed on the screen.
ms
Abbreviation for millisecond(s).
MS-DOS
Abbreviation for Microsoft Disk
Operating System.
MTBF
Abbreviation for mean time between
failures.
multifrequency monitor
A monitor that supports several video
standards. A multifrequency monitor can adjust to the frequency range of the signal from a
variety of video adapters.
mV
Abbreviation for millivolt(s).
NiCad
Acronym for nickel cadmium.
NiMH
Abbreviation for nickel-metal hydride.
NLM
Acronym for NetWare ® Loadable
Module.
NMI
Abbreviation for nonmaskable interrupt.
A device sends an NMI to signal the microprocessor about hardware errors, such as a parity
error.
noninterlaced
A technique for decreasing screen
flicker by sequentially refreshing each horizontal line on the screen.
ns
Abbreviation for nanosecond(s), one
billionth of a second.
NTFS
Abbreviation for the NT File System
option in the Windows NT operating system.
NVRAM
Abbreviation for nonvolatile
random-access memory. Memory that does not lose its contents when you turn off your
computer. NVRAM is used for maintaining the date, time, and system setup options.
OTP
Abbreviation for one-time programmable.
parallel port
An I/O port used most often to connect a
parallel printer to your computer. You can usually identify a parallel port on your
computer by its 25-hole connector.
parameter
A value or option that you specify to a
program. A parameter is sometimes called a switch or an argument.
partition
You can divide a hard-disk drive into
multiple physical sections called partitions with the fdisk command. Each partition can
contain multiple logical drives. For example, you could partition a 200-MB hard-disk drive
into two physically separate partitions with three logical drive assignments, as shown in
the following table.
| Partitioning the Hard-Disk Drive |
Physical Partitions and
Sizes
|
| Partition 1 120 MB Partition 2 80 MB |
| Logical Drive Assignments
and Sizes |
| Drive C 120 MB Drive D 50 MB
Drive E 30 MB |
After partitioning the hard-disk drive,
you must format each logical drive with the format command.
PC Card
Slightly larger than a credit card, a PC
Card is a removable I/O card--such as a modem, LAN, SRAM, or flash memory card--that
adheres to the PCMCIA standards. See also PCMCIA.
PCI
Abbreviation for Peripheral Component
Interconnect. A standard for local-bus implementation developed by Intel Corporation.
PCMCIA
Abbreviation for Personal Computer
Memory Card International Association. See also PC Card.
peripheral device
An internal or external device--such as
a printer, a disk drive, or a keyboard--connected to a computer.
PGA
Abbreviation for pin grid array, a type
of microprocessor socket that allows you to remove the microprocessor chip.
pixel
Arranged in rows and columns, a pixel is
a single point on a video display. Video resolution--640 x 480, for example--is expressed
as the number of pixels across by the number of pixels up and down.
POST
Acronym for power-on self-test. Before
the operating system loads when you turn on your computer, the POST tests various system
components such as RAM, the disk drives, and the keyboard.
ppm
Abbreviation for pages per minute.
PQFP
Abbreviation for plastic quad flat pack,
a type of microprocessor socket in which the microprocessor chip is permanently mounted.
PRN
A synonym for the MS-DOS device name
LPT1.
program diskette set
The set of diskettes from which you can
perform a complete installation of an application program. When you reconfigure a program,
you often need its program diskette set.
protected mode
An operating mode supported by 80286 or
higher microprocessors, protected mode allows operating systems to implement:
- A memory address space of 16 MB (80286 microprocessor) to 4 GB
(Intel386 or higher microprocessor)
- Multitasking
- Virtual memory, a method for increasing addressable memory by using
the hard-disk drive
The Windows NT 32-bit operating system
runs in protected mode. MS-DOS cannot run in protected mode; however, some programs that
you can start from MS-DOS--such as Windows--are able to put the computer into protected
mode.
PS/2
Abbreviation for Personal System/2.
PVC
Abbreviation for polyvinyl chloride.
QIC
Abbreviation for quarter-inch cartridge.
RAM
Acronym for random-access memory. The
computer's primary temporary storage area for program instructions and data. Each location
in RAM is identified by a number called a memory address. Any information stored in RAM is
lost when you turn off your computer.
RAMDAC
Acronym for random-access memory
digital-to-analog converter.
read-only file
A read-only file is one that you are
prohibited from editing or deleting. A file can have read-only status if:
- Its read-only attribute is enabled.
- It resides on a physically write-protected diskette.
- It is located on a network in a directory to which the system
administrator has assigned read-only rights to you.
real mode
An operating mode supported by 80286 or
higher microprocessors, real mode imitates the architecture of an 8086 microprocessor.
Designed to run in real mode, MS-DOS (unassisted by additional software techniques) can
address only 640 KB of conventional memory.
refresh rate
The frequency, measured in Hz, at which
the screen's horizontal lines are recharged. A monitor's refresh rate is also referred to
as its vertical frequency.
REN
Abbreviation for ringer equivalence
number.
RFI
Abbreviation for radio frequency
interference.
RGB
Abbreviation for red/green/blue.
ROM
Acronym for read-only memory. Your
computer contains some programs essential to its operation in ROM code. Unlike RAM, a ROM
chip retains its contents even after you turn off your computer. Examples of code in ROM
include the program that initiates your computer's boot routine and the POST.
rpm
Abbreviation for revolutions per minute.
RTC
Abbreviation for real-time clock.
Battery-powered clock circuitry inside the computer that keeps the date and time after you
turn off the computer.
SCSI
Acronym for small computer system
interface. An I/O bus interface with faster data transmission rates than standard ports.
You can connect up to seven devices to one SCSI interface.
SDMS
Abbreviation for SCSI device management
system.
SDRAM
Abbreviation for Synchronous Dynamic
Random Access Memory.
SECC
Abbreviation for single-edge connector
cartridge.
sec
Abbreviation for second(s).
serial port
An I/O port used most often to connect a
modem or a mouse to your computer. You can usually identify a serial port on your computer
by its 9-pin connector.
shadowing
A computer's system and video BIOS code
is usually stored on ROM chips. Shadowing refers to the performance-enhancement technique
that copies BIOS code to faster RAM chips in the upper memory area (above 640 KB)
during the boot routine.
SRAM
Abbreviation for static random-access
memory. Because SRAM chips do not require continual refreshing, they are substantially
faster than DRAM chips. SRAM is used mostly for external cache memory.
SVGA
Abbreviation for super video graphics
array. See also VGA.
sync negotiation
Sync negotiation is a SCSI feature that
allows the host adapter and its attached SCSI devices to transfer data in synchronous
mode. Synchronous data transfer is faster than asynchronous data transfer.
syntax
The rules that dictate how you must type
a command or instruction so that the computer will understand it.
system board
As the main circuit board, the system
board usually contains most of your computer's integral components, such as the following:
- Microprocessor
- RAM
- Expansion-card connectors
- Controllers for standard peripheral devices, such as the keyboard
- Various ROM chips
Frequently used synonyms for system
board are motherboard and logic board.
system diskette
System diskette is a synonym for
bootable diskette.
system memory
System memory is a synonym for RAM.
System Setup program
System Setup program options allow you
to configure your computer's hardware. Some options in the System Setup program require
that you reboot the computer in order to make a hardware-configuration change. Because the
System Setup program is stored in NVRAM, any options that you set remain in effect until
you change them again.
system.ini file
When you start Windows, it consults the
system.ini file to determine a variety of options for the Windows operating
environment. Among other things, the system.ini file records which video, mouse, and
keyboard drivers are installed for Windows.
Running the Control Panel or Windows
Setup program may change options in the system.ini file. On other occasions, you may need
to change or add options to the system.ini file manually with a text editor, such as
Notepad.
terminator
Some devices, especially disk drives,
contain a terminator to absorb and dissipate excess current. When more than one such
device is connected in a series, you may need to remove the terminator--or change a jumper
setting to disable it--unless it is the last device in the series. However, some devices
have terminators that should never be removed or disabled.
text editor
An application program for editing text
files consisting exclusively of ASCII characters. MS-DOS Editor and Notepad (in Windows)
are text editors, for example. Most word processors use proprietary file formats
containing binary characters, although some can read and write text files.
text mode
See video mode.
TFT
Abbreviation for thin film transistor. A
flat-panel display for notebook computers where each pixel is controlled by one to four
transistors.
tpi
Abbreviation for tracks per inch.
TSR
Abbreviation for
terminate-and-stay-resident. A TSR program runs "in the background." Most TSR
programs implement a predefined key combination (sometimes referred to as a "hot
key") that allows you to activate the TSR program's interface while running another
MS-DOS program. When you finish using the TSR program, you can return to the other
application program and leave the TSR program resident in memory for later use.
Because MS-DOS is not designed to
support multiple programs running simultaneously, TSR programs can sometimes cause memory
conflicts. When troubleshooting, rule out the possibility of such a conflict by rebooting
your computer without starting any TSR programs.
TV
Abbreviation for television.
UL
Abbreviation for Underwriters
Laboratories.
UMB
Abbreviation for upper memory blocks.
See also conventional memory, HMA, memory manager, and upper memory area.
upper memory area
The 384 KB of RAM located between
640 KB and 1 MB. If the computer has an Intel386 or higher microprocessor, a software
utility called a memory manager can create UMBs in the upper memory area, in which you can
load device drivers and memory-resident programs. See also conventional memory, HMA, and
memory manager.
UPS
Abbreviation for uninterruptible power
supply. A battery-powered unit that automatically supplies power to your computer in the
event of an electrical failure.
USOC
Abbreviation for Universal Service
Ordering Code.
utility
A program used to manage system
resources-- memory, disk drives, or printers, for example. The diskcopy command for
duplicating diskettes and the himem.sys device driver for managing extended
memory are utilities included in MS-DOS.
V
Abbreviation for volt(s).
VAC
Abbreviation for volt(s) alternating
current.
VCCI
Abbreviation for Voluntary Control
Council for Interference.
VDC
Abbreviation for volt(s) direct current.
VDE
Abbreviation for Verband Deutscher
Elektrotechniker.
VDS
Abbreviation for Virtual Direct Memory
Access Services.
VESA ®
Acronym for Video Electronics Standards
Association.
VGA
Abbreviation for video graphics array.
VGA and SVGA are video standards for video adapters with greater resolution and color
display capabilities than EGA and CGA, the previous standards.
To display a program at a specific
resolution, you must install the appropriate video drivers and your monitor must support
the resolution. Similarly, the number of colors that a program can display depends on the
capabilities of the monitor, the video driver, and the amount of memory installed for the
video adapter.
VGA feature connector
On some systems with a built-in VGA
video adapter, a VGA feature connector allows you to add an enhancement adapter, such as a
video accelerator, to your computer. A VGA feature connector can also be called a VGA
pass-through connector.
video adapter
The logical circuitry that provides--in
combination with the monitor or display--your computer's video capabilities. A video
adapter may support more or fewer features than a specific monitor offers. Typically, a
video adapter comes with video drivers for displaying popular application programs and
operating environments in a variety of video modes.
On most current Dell computers, a video
adapter is integrated into the system board. Also available are many video adapter cards
that plug into an expansion-card connector.
Video adapters can include memory
separate from RAM on the system board. The amount of video memory, along with the
adapter's video drivers, may affect the number of colors that can be simultaneously
displayed. Video adapters can also include their own coprocessor chip for faster graphics
rendering.
video driver
Graphics-mode application programs and
operating environments, such as Windows, often require video drivers in order to display
at a chosen resolution with the desired number of colors. A program may include some
"generic" video drivers. Any additional video drivers may need to match the
video adapter; you can find these drivers on a separate diskette with your computer or
video adapter.
video memory
Most VGA and SVGA video adapters include
VRAM or DRAM memory chips in addition to your computer's RAM. The amount of video memory
installed primarily influences the number of colors that a program can display (with the
appropriate video drivers and monitor capability).
video mode
Video adapters normally support multiple
text and graphics display modes. Character-based software (such as MS-DOS) displays in
text modes that can be defined as x columns by y rows of characters. Graphics-based
software (such as Windows) displays in graphics modes that can be defined as x horizontal
by y vertical pixels by z colors.
video resolution
Video resolution--640 x 480, for
example--is expressed as the number of pixels across by the number of pixels up and down.
To display a program at a specific graphics resolution, you must install the appropriate
video drivers and your monitor must support the resolution.
virtual 8086 mode
An operating mode supported by Intel386
or higher microprocessors, virtual 8086 mode allows operating environments--such as
Windows--to run multiple programs in separate 1-MB sections of memory. Each 1-MB section
is called a virtual machine.
virtual memory
A method for increasing addressable RAM
by using the hard-disk drive. (MS-DOS does not support true virtual memory, which must be
implemented at the operating system level.) For example, in a computer with 8 MB of RAM
and 16 MB of virtual memory set up on the hard-disk drive, the operating system would
manage the system as though it had 24 MB of physical RAM.
virus
A self-starting program designed to
inconvenience you. Virus programs have been known to corrupt the files stored on a
hard-disk drive or to replicate themselves until a system or network runs out of memory.
The most common way that virus programs
move from one system to another is via "infected" diskettes, from which they
copy themselves to the hard-disk drive. To guard against virus programs, you should do the
following:
- Periodically run a virus-checking utility on your computer's
hard-disk drive
- Always run a virus-checking utility on any diskettes (including
commercially sold software) before using them
VL-Bus
An abbreviation for VESA local bus. A
standard for local bus implementation developed by the Video Electronics Standards
Association.
VLSI
Abbreviation for very-large-scale
integration.
Vpp
Abbreviation for peak-point voltage.
VRAM
Abbreviation for video random-access
memory. Some video adapters use VRAM chips (or a combination of VRAM and DRAM) to improve
video performance. VRAM is dual-ported, allowing the video adapter to update the screen
and receive new image data at the same time.
W
Abbreviation for watt(s).
win.ini file
When you start Windows, it consults the
win.ini file to determine a variety of options for the Windows operating environment.
Among other things, the win.ini file records what printer(s) and fonts are installed for
Windows. The win.ini file also usually includes sections that contain optional settings
for Windows application programs that are installed on the hard-disk drive.
Running the Control Panel or Windows
Setup program may change options in the win.ini file. On other occasions, you may need to
change or add options to the win.ini file manually with a text editor, such as Notepad.
write-protected
Read-only files are said to be
write-protected. You can write-protect a 3.5-inch diskette by sliding its write-protect
tab to the open position and a 5.25-inch diskette by placing an adhesive label over its
write-protect notch.
XMM
Abbreviation for extended memory
manager, a utility that allows application programs and operating environments to use
extended memory in accordance with the XMS. See also conventional memory, EMM, expanded
memory, extended memory, and memory manager.
XMS
Abbreviation for eXtended Memory
Specification. See also EMS, extended memory, and memory manager.
ZIF
Acronym for zero insertion force. Some
computers use ZIF sockets and connectors to allow devices such as the microprocessor chip
to be installed or removed with no stress applied to the device.
|
