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From: abaum (Allen Baum)
Newsgroups: comp.arch
Subject: 040 vs 030 SPEC nos.
Message-ID: <181@armltd.uucp>
Date: 21 May 91 09:49:16 GMT
Sender: abaum@armltd.uucp
Distribution: comp
Organization: A.R.M. Ltd, Swaffham Bulbeck, Cambs, UK
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In article <1991May20.145332.19406@murdoch.acc.Virginia.EDU> clc5q@hemlock.cs.Virginia.EDU (Clark L. Coleman) writes:

>In article <177@armltd.uucp> abaum (Allen Baum) writes:
>>
>>A...there are several reasons why the '040 SPEC numbers are better-
>>1- faster clock, resulting from better process technology,
>
>This does not make any sense to me. The only SPEC numbers for
>the 68040 are for 25MHz chips. There are 68030 chips running at 25MHz
>for several years now, and likewise for the 68882 FPU that went with
>the 68030. Any improvement in SPEC numbers over the 68030 did't come
>from the 68040 having a faster clock rate.

I'm sorry to disappoint you, but the 68040 runs effectively a half
speed bus. A 25Mhz '040 is running at 50Mhz internally. There are,
in fact, two clock pins, one at 25Mhz, and one at 50. For comparison,
you should be comparing 50Mhz '030s and 25Mhz '040s.