From: mccall@mksol.dseg.ti.com (fred j mccall 575-3539)
Subject: Re: OS/2 and SCSI
Organization: Texas Instruments Inc
Date: Thu, 30 Jul 1992 17:42:40 GMT

In <1992Jul30.140855.219272@cs.cmu.edu> jc70@westend.VI.CMU.EDU (Joo C. Chung) writes:

>In article <rick.19.712447261@sjsumcs.sjsu.edu> rick@sjsumcs.sjsu.edu (Richard  
>M. Warner) writes:
>> In article <anderson.13.712329957@mayo.edu> anderson@mayo.edu (Alfred I.  
>Anderson) writes:
>> >From: anderson@mayo.edu (Alfred I. Anderson)
>> >Subject: Re: OS/2 and SCSI
>> >Date: 28 Jul 92 13:25:57 GMT
>> 
>> >In article <1992Jul27.134503.23338@src.umd.edu> chad@src.umd.edu (R Michael  
>McMahon) writes:
>> >>From: chad@src.umd.edu (R Michael McMahon)
>> >>Subject: OS/2 and SCSI
>> >>Date: Mon, 27 Jul 1992 13:45:03 GMT
>> 
>> 
>> >>I have Unix on my PC. Out of curiosity, I got OS/2 2.0 and installed it
>> >>(all 15 disks!) on my 386/7 33Mhz machine with an Adaptec 1542 SCSI
>> >>controller. The disk performance is absolutely unbearable: it sounds 
>> >>like OS/2 is reading one byte at a time from the disk. I believe this 
>> >>is caused by the SCSI setup. Has anyone managed to achieve usable drive 
>> >>performance in a SCSI system??? 
>> 
>> >>I won't use or recommend OS/2 if thats the best it can do.
>> 
>> >>R Michael McMahon       chad@src.umd.edu
>> 
>> 
>> 
>> >Perhaps someone can shed some light on this problem you're having.  I'd be 
>> >interested too.  I wanted to get a 486 clone with a SCSI adapter to use with 
>> >OS/2 Ver 2.  I was told that was a bad idea because IBM does not have a "
>> >virtualized SCSI driver".  I was told to get an IDE disk. 
>> 
>> >Anyone know why?
>> 
>> I'll bite.  Actually, me and my office partner are both running OS/2
>> on 486's with SCSI disk systems (Adaptec controllers, Maxtor drives)
>> and have not had any problems so far.
>> 
>> >^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>> >Alfred Anderson                Internet:    anderson@Mayo.edu
>> >Mayo Foundation - Rochester MN 55905
>> 
>> >NOTE:  PLEASE INCLUDE YOUR RETURN ADDRESS IN THE BODY OR .SIG FILE
>> >OF ANY NOTE SENT TO ME --- THE SOFTWARE ON MY END DOES NOT PASS 
>> >YOUR RETURN ADDRESS FROM THE MESSAGE HEADER TO ME!
>> >-----------------------------------------------------------------

>I have not problems using OS/2 with Adaptec SCSI controllers. I'm using OS/2 on
>2 machines with SCSI controllers. One is a PS/2 with the Adaptec 1640 and the 
>other is a Dell with a 1542. The Dell is a 486/50 and it screams! The PS/2 has
>an internal 60 meg hard drive and an external 213MB scsi hard drive. The
>external drive is about 2-3 times faster than the internal.

The following is from memory.  It may be incorrect in detail, but I
believe that it is essential correct in broad.

I believe the problem is with how the 1542 is set up.  'Out of the
box' behaviour has the timing between the hard and floppy disks set in
such a way that the OS/2 installation fails.  This leads to all the
disk thrashing, etc.  I think you can change the timing on the 1542 by
changing some jumpers on the controller, but I can't state that with
certainty because I don't have this kind of card.

However, I have run OS/2 on my machine at home, which is a 486-50 EISA
with an Adaptec 1740 and a Maxtor 1.2G SCSI drive.  Works like a hose.
My only problem with OS/2 is that the video (or actually, the WPS)
still feels gawdawful slow.

[That and not having a seamless 1024x768x256 ET-4000 driver.]

-- 
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
Newsgroups: comp.os.os2.misc