Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!dcl-cs!aber-cs!pcg
From: pcg@aber-cs.UUCP (Piercarlo Grandi)
Newsgroups: comp.arch
Subject: PC/AT clones with RISC cpu
Message-ID: <2081@aber-cs.UUCP>
Date: 31 Oct 90 18:36:00 GMT
Reply-To: pcg@cs.aber.ac.uk (Piercarlo Grandi)
Organization: Dept of CS, UCW Aberystwyth
	(Disclaimer: my statements are purely personal)
Lines: 56
X-Old-Subject: Re: Tektronix shutdown & move away from 88k's??

On the subject of a SPARC based PC/AT clone:

somebody> It is fairly cheap (starting prices ~$4999).

In article <P0R6UO2@xds13.ferranti.com> peter@ficc.ferranti.com (Peter
da Silva) writes:

peter> Sorry. That's not "fairly cheap". That's not even "moderate". AT
peter> bus machines with 386es in them start under $2000.

On 30 Oct 90 15:45:04 GMT, davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) said:

davidsen> Not with 4MB, FPU, ethernet, and 1152x900 displays, they
davidsen> don't. These are aimed for a totally separate market. I
davidsen> haven't tested one yet, but on paper they will produce better
davidsen> cost/performance than the Sun SS+, at least at list price.

Not to mention an open architecture, with the ability use hundreds of
low cost accessories. But the $4999 really ought to include an hard disk
(say, 80MB ESDI 20msec.) to be competitive with a Sun SLC -- also the OS
may not be included.

davidsen> 25MHz SPARC, FPU, MMU, 64 bit memory path, 64k cache. Color,
davidsen> harddisk, 386, and thinnet are options.

Incidentally, my MIPS PC/AT idea was based on seeing an advert in EDN
for an R3000/R3010 evaluation module that with 64K cache and 128K SRAM
would cost something like $895. This looks expensive, but still it is
significantly less than an i486, or an i386+i387+cache controller, and
gives about the same performance (it is actually better than a 486 on
floating point, as John Mashey keeps telling us).

I have no doubt that a MIPS or SPARC or AMD 29k or M88k based CPU module
should cost significantly less than an i486. Could anyone with an idea
of list prices for quantities like 100 pieces give us an idea of the
cost of a CPU module (CPU, FPU, MMU, minimum effective cache) for each
of the above architectures?

Can anybody tell us how difficult it would be to design a plug in board
for an i486 socket with any of the above chip designs? (I expect this
to be hard).

	Note: i486 motherboards, without the 486, are not much more
	expensive than 386SX ones. Get my drift?

Can anybody tell us how difficult it would be to redesign an existing
i[34]86 based motherboard around each of the aboved chip designs? (I
expect this to be not that difficult, but not easy either).

And so on...


-- 
Piercarlo "Peter" Grandi           | ARPA: pcg%uk.ac.aber.cs@nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcsun!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk