Path: utzoo!utgpu!watmath!iuvax!silver!sl179060
From: sl179060@silver.bacs.indiana.edu (Chima Echeruo)
Newsgroups: comp.binaries.ibm.pc.d
Subject: RISC vs CISC
Message-ID: <29806@iuvax.cs.indiana.edu>
Date: 16 Nov 89 18:02:18 GMT
Sender: root@iuvax.cs.indiana.edu
Distribution: comp.binaries.ibm.pc.d
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I have an IBM AT clone (@ 20Mhz) and sometimes it seems that it is no faster
than an AT (@12Mhz). Most of the bottlenecks seemed to be the disk IO and
the graphics card (8 bit EGA). I expected the 20 Mhz 286 to average 8+ MIPS and
when I ran the MIPS (Chips & Tech) benchmark, I got a disappointing 2.5 - 3.00
MIPS. Does that mean that the 'average' 286 instruction takes 8 cycles?

The Acorn Archimedes A310 (a RISC computer) has a clock rate of 8Mhz yet it
is capable of 4 MIPS. I have been told that the higher the clock rate, the more
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?
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Chima
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