Path: utzoo!attcan!uunet!know!zaphod.mps.ohio-state.edu!wuarchive!emory!gatech!prism!dali!ken
From: ken@dali.gatech.edu (Ken Seefried iii)
Newsgroups: comp.sys.amiga
Subject: Re: UNIX sys V4.0
Message-ID: <16102@hydra.gatech.EDU>
Date: 30 Oct 90 18:30:51 GMT
References: <9010025@hpfcso.HP.COM> <15404@cbmvax.commodore.com> <16001@hydra.gatech.EDU> <15464@cbmvax.commodore.com> <22912@grebyn.com>
Sender: news@prism.gatech.EDU
Reply-To: ken@dali.gatech.edu (Ken Seefried iii)
Organization: The House Of Fun
Lines: 34

In article <22912@grebyn.com> ckp@grebyn.UUCP (Checkpoint Technologies) writes:
>
>But the 030 plus the blitter is able to do bitblits plus run
>applications faster than the 030 alone. This is the reason to
>have a graphics co-processor, so that your applications get more CPU
>because the CPU is spending fewer cycles doing graphics.

This is, of course, absolutely wrong (though it is a common
fallicy).  The actual advantage gained from a graphics coprocessor
depends on many things.  For example, setup time for the graphics
chip can have a big influence on how useful it is.  Another big
area (especially in low-end machines) is memory architecture.
Keith Packard (keith@expo.lcs.mit.edu) is a useful source of hard
data on the relative usefulness of graphics co-processors,
especially under X.   In general, a graphics chip *can* be an
advantage, but it isn't always.  I don't know anything about the
Amiga blitter implimentation, so I can't comment on what may or may
not be it's problems.  

An additional disadvantage of the graphics chips is that, being
somewhat specialty items, they do not track advances in technology
as fast a general purpose CPUs.

>Now if you tell me that the 030 alone *can* run applications and do
>graphics faster than the 030 plus the blitter, well then I won't believe
>you...

Never good to make statements like that when totally lacking hard
evedence...

--
	ken seefried iii	"A snear, a snarl, a whip that
	ken@dali.gatech.edu	 stings...these are a few of
				 my favorite things..."