Dell PRECISION 530 - Manual (Page 285)

Glossary 285
Glossary
A
Ampere. A measurement of current in an electrical
conductor.
AC
Alternating current. Electricity that reverses its
direction at a rate of 60 times per second (50 times
per second in some countries). See DC .
Accelerator
A computer component that enhances the processing
speed of a particular device , usually by taking over
some of the tasks originally assigned by that device.
For example, a video accelerator card will take over
some of the graphic functions originally assigned to
the microprocessor .
ACPI
Advanced Configuration and Power Interface. An
industry standard developed by Intel
®
, Microsoft
®
,
and Toshiba for computer power management. The
key element of the standard is that the OS controls
power management. In previous standards, most of
the power management tasks were run by the BIOS ,
with limited intervention by the OS. In ACPI, the
BIOS communicates with hardware components in
the computer, but the OS controls power
management operations.
AGP
Accelerated graphics port. A high-speed graphics port
that produces fast communication between the
graphics controller and computer. It allows the video
controller to directly access the computer's main
memory and bypass the PCI bus. A video expansion
card installed in this port can run almost twice as fast
as that in a PCI slot. This also helps to reduce the
traffic on the PCI bus.
ANSI
American National Standards Institute. An
organization that publishes standards for data
alphabets, codes, and signaling schemes. See ISO .
API
Application Program Interface. The interface through
which an application program accesses the OS and
other services.
APIC
Advanced programmable interrupt controller.
Prioritizes and manages IRQs for the various devices
in a PC . Without an APIC, the microprocessor must
control IRQs.
ASCII
American Standard Code for Information Interchange.
The basis of character sets used in many present-day
computers. ASCII can be used to convey some
control codes , the space character, numbers, most
basic punctuation, and unaccented lower- and upper-
case letters.
AT
Advanced Technology. An IBM® PC introduced in
1984 that has an Intel 80286 microprocessor , 16-bit
bus , and 1.2 MB diskette drive.
ATA
Advanced Technology Attachment. A specification for
drive interface. See IDE .