Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!tank!mimsy!tove.umd.edu!steveg From: steveg@tove.umd.edu (Steve Green) Newsgroups: comp.sys.mac Subject: Re: The PMMU on the Mac II Keywords: PMMU, 68851, Macintosh II Message-ID: <16197@mimsy.UUCP> Date: 3 Mar 89 17:10:29 GMT References: <2295@unmvax.unm.edu> <2904@nunki.usc.edu> Sender: nobody@mimsy.UUCP Reply-To: steveg@tove.umd.edu.UUCP (Steve Green) Distribution: na Organization: U of Maryland, Dept. of Computer Science, Lines: 7 The pmmu from apple is just the 68851rc16. The 16 is the speed (mhz). The pmmu replaces the BIG BLACK CHIP. That is, the only big black chip in a socket. There is no compatability problems as the mac os ignors it completely. (for now) Warning: The pmmu's pin 1 is not in the same orientation as the pin 1 of the cpu, look carefully when installing this at the markings on the board and the notch on the socket for the pin 1 position.