Dell GX620 - 3.6GHz Desktop 1GB RAM 80GB Windows XP SFF, Руководство пользователя

Страница: 309 / 352

Glossary 309
local bus that supports 32-and 64-bit data paths, providing a
high-speed data path between the processor and devices
such as video, drives, and networks.
P C M C I A — Personal Computer Memory Card
International Association — The organization that
establishes standards for PC Cards.
P I N — personal identification number — A sequence of
numerals and/or letters used to restrict unauthorized access
to computer networks and other secure systems.
P I O — programmed input/output — A method of
transferring data between two devices through the processor
as part of the data path.
P I X E L
— A single point on a display screen. Pixels are
arranged in rows and columns to create an image. A video
resolution, such as 800 x 600, is expressed as the number of
pixels across by the number of pixels up and down.
P
L U G
-
A N D
- P
L A Y
— The ability of the computer to
automatically configure devices. Plug and Play provides
automatic installation, configuration, and compatibility with
existing hardware if the BIOS, operating system, and all
devices are Plug and Play compliant.
P O S T — power-on self-test — Diagnostics programs,
loaded automatically by the BIOS, that perform basic tests
on the major computer components, such as memory, hard
drives, and video. If no problems are detected during POST,
the computer continues the start-up.
P R O C E S S O R
— A computer chip that interprets and
executes program instructions. Sometimes the processor is
referred to as the CPU (central processing unit).
P R O G R A M
— Any software that processes data for you,
including spreadsheet, word processor, database, and game
packages. Programs require an operating system to run.
P S / 2 — personal system/2 — A type of connector for
attaching a PS/2-compatible keyboard, mouse, or keypad.
P X E — pre-boot execution environment — A WfM
(Wired for Management) standard that allows networked
computers that do not have an operating system to be
configured and started remotely.
R
R A I D — redundant array of independent disks — A
method of providing data redundancy. Some common
implementations of RAID include RAID 0, RAID 1,
RAID 5, RAID 10, and RAID 50.
R A M — random-access memory — The primary
temporary storage area for program instructions and data.
Any information stored in RAM is lost when you shut down
your computer.
R E A D M E F I L E
— A text file included with a software
package or hardware product. Typically, readme files
provide installation information and describe new product
enhancements or corrections that have not yet been
documented.
R E A D
- O
N L Y
— Data and/or files you can view but
cannot edit or delete. A file can have read-only status if:
• It resides on a physically write-protected floppy disk,
CD, or DVD.
• It is located on a network in a directory and the system
administrator has assigned rights only to specific
individuals.
R E F R E S H R A T E
— The frequency, measured in Hz, at
which your screen's horizontal lines are recharged
(sometimes also referred to as its
vertical frequency ). The
higher the refresh rate, the less video flicker can be seen by
the human eye.
R E S O L U T I O N
— The sharpness and clarity of an image
produced by a printer or displayed on a monitor. The higher
the resolution, the sharper the image.
R F I — radio frequency interference — Interference that is
generated at typical radio frequencies, in the range of 10
kHz to 100,000 MHz. Radio frequencies are at the lower
end of the electromagnetic frequency spectrum and are
more likely to have interference than the higher frequency
radiations, such as infrared and light.
R O M — read-only memory — Memory that stores data
and programs that cannot be deleted or written to by the
computer. ROM, unlike RAM, retains its contents after you
shut down your computer. Some programs essential to the
operation of your computer reside in ROM.
R P M — revolutions per minute — The number of