Laptop User Manual

Glossary 153
DDR2 SDRAM — double-data-rate 2 SDRAM — A type
of DDR SDRAM that uses a 4-bit prefetch and other
architectural changes to boost memory speed to over 400
MHz.
device — Hardware such as a disk drive, printer, or
keyboard that is installed in or connected to your
computer.
device driver — See driver.
DIMM — dual in-line memory module — A circuit board
with memory chips that connects to a memory module on
the system board.
DIN connector — A round, six-pin connector that
conforms to DIN (Deutsche Industrie-Norm) standards;
it is typically used to connect PS/2 keyboard or mouse
cable connectors.
disk striping — A technique for spreading data over
multiple disk drives. Disk striping can speed up operations
that retrieve data from disk storage. Computers that use
disk striping generally allow the user to select the data
unit size or stripe width.
DMA — direct memory access — A channel that allows
certain types of data transfer between RAM and a device
to bypass the processor.
docking device — See APR.
DMTF — Distributed Management Task Force — A
consortium of hardware and software companies who
develop management standards for distributed desktop,
network, enterprise, and Internet environments.
domain — A group of computers, programs, and devices
on a network that are administered as a unit with common
rules and procedures for use by a specific group of users. A
user logs on to the domain to gain access to the resources.
DRAM — dynamic random-access memory — Memory
that stores information in integrated circuits containing
capacitors.
driver — Software that allows the operating system to
control a device such as a printer. Many devices do not
work properly if the correct driver is not installed in the
computer.
DSL — Digital Subscriber Line — A technology that
provides a constant, high-speed Internet connection
through an analog telephone line.
dual-core — A technology in which two physical
computational units exist inside a single processor
package, thereby increasing computing efficiency and
multi-tasking ability.
dual display mode — A display setting that allows you to
use a second monitor as an extension of your display. Also
referred to as extended display mode.
DVD-R — DVD recordable — A recordable version of a
DVD. Data can be recorded only once onto a DVD-R.
Once recorded, the data cannot be erased or written over.
DVD+RW — DVD rewritable — A rewritable version of
a DVD. Data can be written to a DVD+RW disc, and
then erased and written over (rewritten). (DVD+RW
technology is different from DVD-RW technology.)
DVD+RW drive — drive that can read DVDs and most
CD media and write to DVD+RW (rewritable DVDs)
discs.
DVI — digital video interface — A standard for digital
transmission between a computer and a digital video
display.
E
ECC — error checking and correction — A type of
memory that includes special circuitry for testing the
accuracy of data as it passes in and out of memory.
ECP — extended capabilities port — A parallel connector
design that provides improved bidirectional data
transmission. Similar to EPP, ECP uses direct memory
access to transfer data and often improves performance.
EIDE — enhanced integrated device electronics — An
improved version of the IDE interface for hard drives and
CD drives.
EMI — electromagnetic interference — Electrical
interference caused by electromagnetic radiation.
ENERGY STAR
®
— Environmental Protection Agency
requirements that decrease the overall consumption of
electricity.
EPP — enhanced parallel port — A parallel connector
design that provides bidirectional data transmission.