154 Dell PowerEdge 2100/180 and 2100/200 Systems User’s Guide
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 and embedded 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 prompt normally in-
dicates 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 com-
puter. To use the diskette-based diagnostics, you must boot
your computer from the Dell Diagnostics Diskette. Refer to
your Diagnostics 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 As-
sociation 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 capac-
ity) 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.
DIP switches
root directory
subdirectories