Users Guide

152 Glossary
video adapter
The logical circuitry that provides—in combination with
the monitor—your system'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 systems in a variety of video modes.
On some systems, 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 often 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 for faster graphics rendering.
video driver
A program that allows graphics-mode application
programs and operating systems to display at a chosen
resolution with the desired number of colors. A
software package may include some "generic" video
drivers. Any additional video drivers may need to match
the video adapter installed in the system.
video memory
Most VGA and SVGA video adapters include memory
chips in addition to your system'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 capabilities).
video mode
Video adapters normally support multiple text and
graphics display modes. Character-based software
displays in text modes that can be defined as
x columns
by
y rows of characters. Graphics-based software
displays in graphics modes that can be defined as
x
horizontal by
y vertical pixels by z colors.
video resolution
Video resolution—800 x 600, 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 memory
A method for increasing addressable RAM by using the
hard drive. For example, in a system with 16 MB of
RAM and 16 MB of virtual memory set up on the hard
drive, the operating system would manage the system
as though it had 32 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 drive or to replicate themselves until
a computer 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 drive. To guard
against virus programs, you should do the following:
• Periodically run a virus-checking utility on your
system's hard drive
• Always run a virus-checking utility on any
diskettes (including commercially sold software)
before using them
VLSI
Abbreviation for very-large-scale integration.
VLVESA
Acronym for very low voltage enterprise
system architecture.
vpp
Abbreviation for peak-point voltage.
VRAM
Acronym 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.
VRM
Abbreviation fro voltage regulator module.