Dell PowerEdge 6350 User Manual page 136

16 Dell PowerEdge 6350 Systems User's Guide
Abbreviation for Virtual Direct Memory
Access Services.
Acronym for Video Electronics Standards
Association.
Abbreviation for video graphics array. VGA
and SVGA are video standards for video
adapters with greater resolution and color
display capabilities than EGA and CGA,
the previous standards.
To display a program at a specific resolu-
tion, you must install the appropriate
video drivers and your monitor must sup-
port the resolution. Similarly, the number
of colors that a program can display de-
pends on the capabilities of the monitor,
the video driver, and the amount of mem-
ory installed for the video adapter.
On some systems with a built-in VGA
video adapter, a VGA feature connector
allows you to add an enhancement adapt-
er, such as a video accelerator, to your
computer. A VGA feature connector can
also be called a VGA pass-through
connector .
The logical circuitry that provides—in
combination with the monitor or display—
your computer'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 envi-
ronments in a variety of video modes.
On most current Dell computers, 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 can include memory sep-
arate 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
chip for faster graphics rendering.
Graphics-mode application programs and
operating environments, such as Win-
dows, often require video drivers in order
to display at a chosen resolution with the
desired number of colors. A program may
include some "generic" video drivers.
Any additional video drivers may need to
match the video adapter; you can find
these drivers on a separate diskette with
your computer or video adapter.
Most VGA and SVGA video adapters in-
clude VRAM or DRAM memory chips in
addition to your computer's RAM. The
amount of video memory installed prima-
rily influences the number of colors that a
program can display (with the appropriate
video drivers and monitor capability).
Video adapters normally support multiple
text and graphics display modes. Charac-
ter-based software (such as MS-DOS)
displays in text modes that can be defined
as x columns by y rows of characters. Graph-
ics-based software (such as Windows)
displays in graphics modes that can be de-
fined as x horizontal by y vertical pixels by z
colors.
Video resolution—640 x 480, for exam-
ple—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 moni-
tor must support the resolution.
An operating mode supported by Intel386
or higher microprocessors, virtual 8086
mode allows operating environments—
such as Windows—to run multiple pro-
grams in separate 1-MB sections of
memory. Each 1-MB section is called a
virtual machine .