Path: utzoo!dptcdc!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.arch
Subject: Re: 486 and 68040
Message-ID: <6629@cbmvax.UUCP>
Date: 18 Apr 89 23:16:45 GMT
References: <12435@reed.UUCP>
Organization: Commodore Technology, West Chester, PA
Lines: 18

in article <12435@reed.UUCP>, mdr@reed.UUCP (Mike Rutenberg) says:

> From my memory, the other things that stand out about the i486:

> 	* the on-chip fpu is much faster than the 80387.  It was unclear
> 	  if this was due simply to being on-chip or whether it involved
> 	  architecture changes to the fpu.

If you did nothing else, moving the math chip on-board would speed things
up several times.  Just the delays in crossing an external bus make a big
difference.  Inside a chip, gate delays are on the order of 1ns or better,
outside on the order of 10ns.

> Mike Rutenberg      Reed College, Portland Oregon     (503)239-4434 (home)
-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
              Amiga -- It's not just a job, it's an obsession