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Date: Thu, 5 Sep 1996 21:53:32 +0200 (MET DST)
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From: Stefan Esser <se@zpr.uni-koeln.de>
To: Torbjorn Granlund <tege@matematik.su.se>
Cc: Sean Eric Fagan <sef@kithrup.com>, bde@zeta.org.au, hackers@freebsd.org
Subject: Re: forwarded 
In-Reply-To: <199609051257.OAA16458@insanus.matematik.su.se>
References: <199609042128.OAA28324@kithrup.com>
	<199609051257.OAA16458@insanus.matematik.su.se>
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Torbjorn Granlund writes:
 > For completeness, here is my system setup:
 > 
 >   ASUS P/I-P55TP4N (P167, 512KB burst cache, 64MB EDO DRAM)
 >   Adaptec 2940UW PCI
 >     Fujitsu 2954SAU 4.4GB (8-bit Ultra enabled)
 >     HP35480A DAT (Fast SCSI)
 >     Toshiba XM-3701TA CD-ROM (Fast SCSI) (last device, terminated)

Hmmm, what's the length of the SCSI cable ?
What quality is it ?

I assume you know, that Ultra-SCSI tolerates at 
most 1.5 (5ft.) of high-quality cable, total.
But if your cable is not exactly up to the 
requirements of the spec, I'd be careful not to 
go beyond half that length.

Another (IMHO) open question is, whether FAST
SCSI devices (like your DAT and CDROM) may be
on a SCSI bus using 20MHz transfer rates. I'd
be careful because of a perhaps too high load,
and because they might become confused because
of the too short strobes.

(I do not have hard facts that such a configuration
is unreliable, but I have observed similar problems
when FAST SCSI first appeared, a few years ago ...)

Regards, STefan