File:VLSI VI475 HMMU from Macintosh II bottom.jpg

Bottom of a VLSI VI475 hardware memory management unit (HMMU) from a stock Macintosh II. It only occupies 70 out of 132 pins of a Motorola 68851 socket and does not provide virtual memory support to the 68020 processor.

Also known as "Apple HMMU" or "HMMU Chip". Apple part number: 343-0002-1.

Source

 * File:VLSI VI475 HMMU chip from an Apple Macintosh II - back.jpg by Gona.eu, Wikimedia Commons. 2009-05-08 / 2009-04-19.