Source : Free On-Line Dictionary of Computing

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.
     
        {A VRAM Song (http://www.fweep.com/vram.html)}!
     
        (2001-02-14)