Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!xstor!iverson
From: iverson@xstor.UUCP (Tim Iverson)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: SCSI Board Info Request
Message-ID: <209@xstor.UUCP>
Date: 10 Oct 90 18:42:50 GMT
References: <9254@orca.wv.tek.com> <1990Oct07.173315.6532@nstar.uucp>
Reply-To: iverson@xstor.UUCP (Tim Iverson)
Organization: Storage Dimensions, Inc.
Lines: 32

In article <1990Oct07.173315.6532@nstar.uucp> larry@nstar.uucp (Larry Snyder) writes:
>The best SCSI controller available for AT bus machines is the
>Adaptec 1542B.  By best - the 1542 yields the fastest throughput
>under 386 Unix (Interactive) and DOS,

True for Unix, very false for DOS.  The non-intelligent boards are much
faster than the 154xB series on a single-threaded OS (e.g. DOS) due to the
high overhead on each command: about 2ms per command for the 1542B.  There
are also fewer integration problems since you don't have to worry about the
1st party DMA getting thrown for a loop by the 386 memory managers.

Of course, as bad as the 1542 is for DOS, it's just about the best you can
find for Unix - almost all support it with a native driver (for some it's
the only SCSI board you can boot from), and it provides some very helpful
features to boost performance under Unix.  There are boards that do much
better, but they do not have the widespread acceptance that the 1542 has.

>Several folks with the WD 1007 FAST controllers have reported
>problems with a lack of support - and slower throughput..

The WD7000 FASST board performs about the same as the 1542 under DOS; I
don't know how well it does under Unix - I've never seen a driver for it.
I last used one about 6 months ago, when I had to try three different boards
before finding just one that worked and had to do the integration with a
non-wd board because their own software (by Columbia Data) wouldn't work
correctly with the 7000.

> Larry Snyder, Northern Star Communications, Notre Dame, IN USA 
> {larry@nstar, uunet!sco!romed!nstar!larry, nstar!larry@ndmath.math.nd.edu}

- Tim Iverson
  uunet!xstor!iverson