Newsgroups: comp.sys.ibm.pc.hardware
Path: utzoo!censor!meadow!py
From: py@meadow.uucp (Peter Yeung)
Subject: Re: Need help!!! 2 Unconnected Questions
Message-ID: <1990Nov14.161103.28168@meadow.uucp>
Reply-To: py@meadow.UUCP (Peter Yeung)
Organization: Amdahl Canada Ltd., Software Development Center
References: <5451@tuminfo1.lan.informatik.tu-muenchen.dbp.de> <90313.163500RICK@MAINE.BITNET>
Distribution: comp
Date: Wed, 14 Nov 90 16:11:03 GMT

In article <90313.163500RICK@MAINE.BITNET> RICK@MAINE.BITNET writes:
>I have been given the challenge of choosing the upgrade choice
>for my University.  Can any of you tell me where to get
>new mother boards or turbo expantion, coprocesser or processer,
>for several types of compatables; Epson, Zmax, AT&T 6300, Zenith,
>IBM PC's and Packard Bell computers.  Could you tell me the
>problems associated, pricing, dealers, and experiences you
>have had with any of these situations.  Thanks
> 

If those are straight 4.77 MHz 8088 based machines, I think there are people
still selling "accelerator cards" for XT type of machines. I was using a card
call "BreakThru 286" which replaced the 8088 chip with a 286. A friend of mine
was using Microsoft Mach 20 which also replaced the 800 with a 286. However,
the prices of clone motherboards have came down so much, it would be much
cheaper to replace the complete motherboard. E.g., I paid CAN$600 for the
BreakThru 286 while you can get a clone 12 MHz 286 motherboard for about
CAN$200. However, the catch is that most of those motherboards fit only
layout of 100% XT compatibles. The problem with accelerator cards is that
I have not seen any ads for quite a while.

The BreakThru 286 I was using worked quite well and was very reliable. 
I had even changed the 8MHz crystal to 10MHz without any problems. It is still 
being used occasionally. The only incompatibility I have experienced was that
I bought a floppy with built in driver in PROM such that one can use high
density floppy drives in an XT. Somehow, the driver was written such that when
it detected a 286, it assumed it was an AT and started addressing various (DMA?)
ports in an AT. Obviously, it did not work on an XT.


-- 
Peter Yeung     Amdahl Canada Ltd., Software Development Center
                2000 Argentia Road, Plaza 2, Suite 300
                Mississauga, Ont.   L5N 1V8
                Phone: (416) 542-6300    Fax: (416) 858-2233