Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!pasteur!ucbvax!ucdavis!deneb.ucdavis.edu!ecs175f037 From: ecs175f037@deneb.ucdavis.edu (Greg DeMichillie) Newsgroups: comp.sys.mac Subject: Re: 1.75Mb Mac Plus possible? Summary: No, you must but SIMMS in two at a time Message-ID: <3366@ucdavis.ucdavis.edu> Date: 8 Dec 88 21:10:46 GMT References: <870265@hpcilzb.HP.COM> Sender: uucp@ucdavis.ucdavis.edu Reply-To: lgdemichillie@ucdavis.edu (Greg DeMichillie) Organization: University of California, Davis Lines: 34 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? It sure would be nice on my pocket book if I could upgrade one SIMM >at a time. > >Chris Christensen Sorry, but when adding SIMMS to a Mac Plus or SE you must add them in pairs. That means that these are the possible combinations: Bank A Bank B 256K 256K 256K 256K = 1MB 256K 256K 1MB 1MB = 2.5MB 1MB 1MB 1MB 1MB = 4 MB It is technically possible to have this also: empty empty 1MB 1MB = 2MB although that would mean throwing away the .5MB that was already in you Mac. This is how Apple makes the Mac SE 2/40. You can use third party memory expansion kits that piggy-back another pair of 256K SIMMS onto the existing 256K ones. That would give you a total of 2MB but that is not Apple supported or recommended. And you'd have to throw them away to go to 4MB later on anyway. ----- Greg DeMichillie Apple Student Rep - UC Davis lgdemichillie@ucdavis.edu ucbvax!ucdavis!lgdemichillie AppleLink:ST0178 Disclaimer: If you've seen one disclaimer, you've seen them all.