Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!spool.mu.edu!uunet!comp.vuw.ac.nz!canterbury!otago.ac.nz!michael
From: michael@otago.ac.nz
Newsgroups: comp.sys.mac.hardware
Subject: Re: The LC vs. IIsi (CPUs)
Message-ID: <1991Jun8.141945.496@otago.ac.nz>
Date: 8 Jun 91 02:53:54 GMT
References: <1991Jun5.175401.14345@sequent.com> <1991Jun7.192453.11305@dartvax.dartmouth.edu>
Organization: University of Otago, Dunedin, New Zealand
Lines: 37

In article <1991Jun7.192453.11305@dartvax.dartmouth.edu>, Brian.V.Hughes@dartmouth.edu (Brian V. Hughes) writes:

>     The IISi comes with 1 Meg soldered to the mother board and 4 SIMM
> slots that must be filed with the same type of SIMM. This is a function
> of the 68030 architecture. It only recognizes memory in banks of four.
> Becuase the LC is an 020 it can handle bakes of two. The IIsi can

I'm afraid its nothing to do with the '020 v '030. Both CPUs have dynamic bus
sizing and will talk to any width of RAM *if* the hardware design is set up to
do this. The LC has been designed with 16-bit wide RAM to cut costs. The IIsi
has 32-bit wide because its faster. Both of them would work with other widths
of RAM if the hardware told them to. One could (I presume) stick a 32-bit wide
RAM expansion card in an LC and get a speed-up as well as the additional
capacity...

>> 2) Video performance

The most important difference for my money is that the IIsi will drive the
Portrait display and the LC won't...

> an 030 PDS adaptor (the same slot in the SE30). Both of the adaptor
> cards comes with a 16 mHz 68882 math co-processor, that will improve
> the speed of many functions, the most important of which is probably
> spreadsheet programs.

Mmph. I have trouble thinking of many "other functions". The Finder, no. I
would be surprised if any word processors would gain the slightest advantage
from the FPU. CAD packages, yes. MacDraw, anyone?


Michael(tm) Hamel, Computing Services Centre, University of Otago, New Zealand

HAMBLEDON (n.)                     
The sound of a single-engined aircraft flying by, heard whilst lying in a
summer field in England, which somehow concentrates the silence and sense
of space and timelessness and leaves one with a profound feeling of
something or other.