Path: utzoo!utgpu!watmath!clyde!ima!think!ephraim
From: ephraim@think.COM (Ephraim Vishniac)
Newsgroups: comp.sys.mac
Subject: Re: 1.75Mb Mac Plus possible?
Message-ID: <33209@think.UUCP>
Date: 9 Dec 88 15:03:42 GMT
References: <870265@hpcilzb.HP.COM>
Sender: news@think.UUCP
Reply-To: ephraim@think.com (Ephraim Vishniac)
Organization: Thinking Machines Corporation, Cambridge MA, USA
Lines: 16

In article <870265@hpcilzb.HP.COM> cnc@hpcilzb.HP.COM (Chris Christensen) writes:

>I have always heard about making a 2.5Mb Mac+ or a 4Mb one.  Can you
>replace one of the SIMMs to get a 1.75Mb machine or three to get a
>3.25Mb one? Or is there something magical about replacing an even
>number of them?

Yes, there is.  The Plus and SE have a 16-bit bus.  SIMMs are 8 bits
wide.  Similarly, the Mac II's 32-bit bus requires that you install
SIMMs in identical groups of four.

Ephraim Vishniac					  ephraim@think.com
Thinking Machines Corporation / 245 First Street / Cambridge, MA 02142-1214

     On two occasions I have been asked, "Pray, Mr. Babbage, if you put
     into the machine wrong figures, will the right answers come out?"