Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!uflorida!ukma!rutgers!cs.utexas.edu!uunet!ficc!peter
From: peter@ficc.uu.net (Peter da Silva)
Newsgroups: comp.arch
Subject: Re: 68020 vs. 68030 speed (was Re: 80486 vs. 68040 code size)
Message-ID: <4175@ficc.uu.net>
Date: 13 May 89 00:52:10 GMT
References: <922@aber-cs.UUCP> <8081@killer.Dallas.TX.US> <700@tukki.jyu.fi>
Distribution: eunet,world
Organization: Xenix Support
Lines: 20

One thing you have to keep in mind in the 80386 versus 68030 debate is
that, yes, there are fewer 68030 systems out there then 80386 boxes...
but the vast majority of the 80386 systems are crippled by the poor
performance of the AT bus. I have been benchmarking a 25 MHz 386 against
our 16 Mhz 80286es on multibus. The speed advantage of the 80386 is
almost entirely lost in the low performance of the bus. In fact many
of our development tools run faster on the 286 or on a 386 in 286 mode
on the multibus.

If you just compare the market share of high-performance 80386 versus
68030 boxes the balance swings way back the other way. And once you leave
behind AT-bus compatibility and cheap AT peripherals there's no reason
to stick to the 80386. Either RISC, or if you're conservative the motorola
chips, are far better. At least motorola doesn't have a history of abandoning
their entire architecture every time they come out with a new chip.
-- 
Peter da Silva, Xenix Support, Ferranti International Controls Corporation.

Business: uunet.uu.net!ficc!peter, peter@ficc.uu.net, +1 713 274 5180.
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