Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!apple!dwells From: dwells@Apple.COM (Dave Wells) Newsgroups: comp.sys.mac Subject: Re: Nix on mixing memory speeds? Message-ID: <34977@apple.Apple.COM> Date: 23 Sep 89 22:04:20 GMT References: <11979@cit-vax.Caltech.Edu> <4002@phri.UUCP> <2040@leah.Albany.Edu> <11900@polya.Stanford.EDU> Distribution: usa Organization: Apple Computer Inc, Cupertino, CA Lines: 32 In article <11900@polya.Stanford.EDU> kaufman@Neon.Stanford.EDU (Marc T. Kaufman) writes: >I rise to Roy Smith's defense. That IS a constructive comment -- to the >effect that: the folklore that says you can't mix memory speeds (subject to >the requirement that each memory module is itself adequately fast) -- is >Bullshit. > >Now I know that one doesn't have to be an EE to own and operate a computer. >But we don't have to be afraid of them, either. There is a lot of tolerance >in the design of a computer just so spot shortages of a particular chip, or >a low-tolerance part, won't make the machine unbuildable. That's why so many >(IBM) clone makers can push nominal 16 MHz machines to 20MHz -- as long as >you don't get them too hot. > >If you want to cause trouble, why don't we start the rumor that using faster >memory chips will invalidate the FCC clearance because the faster rise times >radiate more... It is possible for mixed speed RAM in a bank to cause malfunctions. In a former life I was in tech support for a small accelerator company. While I was there, we discovered that combinations of different speed (and sometimes manufacturer) RAM would cause the Mac to go out to lunch. This wasn't a one time incident, and all of the RAM in use was rated at or above spec. The Mac's would occassionally die when we mixed some brands/speeds of RAM within banks. (Hey, don't worry. I'm not an EE ;-] ) -Dave -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Dave Wells, Apple Computer, Inc. MS: 37-Y (408) 974-5515 Mail: dwells@apple.com or AppleLink d.wells or GEnie D.WELLS These opinions may be nothing more than the ramblings of a fatigued tinkerer -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-