Path: utzoo!utgpu!watmath!att!rutgers!ucsd!ucbvax!pasteur!dorothy.Berkeley.EDU!cs9a-ax
From: cs9a-ax@dorothy.Berkeley.EDU (Mike Morrison)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: RISC vs CISC
Message-ID: <19648@pasteur.Berkeley.EDU>
Date: 16 Nov 89 21:25:42 GMT
References: <29806@iuvax.cs.indiana.edu>
Sender: news@pasteur.Berkeley.EDU
Reply-To: cs9a-ax@dorothy.Berkeley.EDU.UUCP (Mike Morrison)
Distribution: comp.binaries.ibm.pc.d
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In article <29806@iuvax.cs.indiana.edu> sl179060@silver.bacs.indiana.edu (Chima Echeruo) writes:

>expensive the hardware (eg. 33 Mhz 386 vs 16 Mhz). If this is so why does INTEL
>keep raising the clock speeds on their chips? Would it not be cheaper and more
>efficient to modify their chips to make use of the RISC technology?
>
>Would the RISC 286 (@10 Mhz) not outperform the CISC 286 (@20)? What are the
>factors involved in the decision to make a chip RISC or CISC?
>-----
>Chima
>-----

RISC stands for Reduced Instruction Set Computer, and CISC stands for Complex(?)
Instruction Set Computer.  It is impossible to make a "RISC 286"
since this would mean modifying the instruction set, which would render all of
the available software useless -- if you change the instruction set it is no
longer a '286.

There are also those who say that the 8086 series IS RISC.  I don't buy it
though.

Mike Morrison
cs9a-ax@dorothy.berkeley.edu
morrison@ocf.berkeley.edu