random access memory

n : the most common computer memory which can be used by

programs to perform necessary tasks while the computer is

on; an integrated circuit memory chip allows information

to be stored or accessed in any order and all storage

locations are equally accessible [syn: {random-access

memory}, {random memory}, {RAM}, {read/write memory}]

video random access memory

(VRAM) Fast memory designed for storing the image

to be displayed on a computer's {monitor}. VRAM may be built

from special memory {integrated circuits} designed to be

accessed sequentially.

VRAM must be fast enough to supply data to the display

electronics at the speed at which the screen is scanned. Thus

for example, for a {resolution} of 1280x1024 eight-bit

{pixels} at a {refresh rate} of 70 Hz, the {video memory}

would need to supply 1280x1024x70 ◦ 90 Mbyte/s or one byte

every 11 ns. The VRAM may be {dual ported} in order to allow

the display electronics and the {CPU} to access it at the same

time.

In an {IBM PC} the VRAM is located on the display interface

card and 0.5 - 2 MB is typical.

(1995-03-14)