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From: Terry Lambert <terry@lambert.org>
Message-Id: <199705241756.KAA11028@phaeton.artisoft.com>
Subject: Re: Controler for SCSI
To: bde@zeta.org.au (Bruce Evans)
Date: Sat, 24 May 1997 10:56:12 -0700 (MST)
Cc: hackers@FreeBSD.ORG, j@uriah.heep.sax.de
In-Reply-To: <199705241036.UAA02991@godzilla.zeta.org.au> from "Bruce Evans" at May 24, 97 08:36:00 pm
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> >> Funny, the 2920 is listed in the docs somewhere as not supported <the
> >> only Adaptec so specified>.
> >...
> >The EIDE is about the same as what you could get with the Future
> >Domain; both are PIO only.
> 
> Nope, EIDE supports PIO mode 4 (16.6MB/sec) and DMA at about the same
> speed.  16.6MB/sec is standard for PCI EIDE controllers.  Crufty SCSI
> PIO controllers are unlikely to be as fast.  New Quantum EIDE drives
> support DMA at 33.3MB/sec.

Except while doing PIO, your CPU is neglecting the number crunching
it is supposed to be doing instead.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.