High performance coprocessor boards of the 80s and 90s - was Re: SGI ONYX

Guy Sotomayor ggs at shiresoft.com
Thu Apr 21 16:30:54 CDT 2016

> On Apr 21, 2016, at 2:13 PM, Swift Griggs <swiftgriggs at gmail.com> wrote:
> On Thu, 21 Apr 2016, Guy Sotomayor wrote:
>> Let?s not also forget the various 370 and 390 co-processor boards that
>> could be put into PC?s at various times to allow one to turn the PC into a
>> small mainframe capable of running mainframe software (including the OS).
> I can't forget because I never knew that!  I'm not always that interested in
> IBM 3x0 systems, but that's a really cool concept.  I'm guessing they were
> microchannel boards that plugged into the IBM PS/2 line ?  I can't believe
> IBM would have let you run them on any old PC (given the clone wars at the
> time).  That blows my mind.

Actually, the first one was called XT/370 because it plugged into an XT!
Then came AT/370.  Those were obviously ISA boards.  Then came some
variants that were microchannel.  The final iterations were PCI based.

The microchannel and PCI based boards went into systems that ran OS/2
or AIX (P/390 and R/390 respectively).

IBM didn’t sell the boards separately from the system (ie they delivered all of
the HW).  There were also various licenses (uCode for the 390 board and
various drivers for AIX (RS/6000 only) and OS/2.  And then of course there
was the OS that you had to license from IBM (which generally was about the
same cost as the HW…I think the base OS/390 was ~$28,000 (that’s just the
OS folks…you still needed the HW).

TTFN - Guy

More information about the cctalk mailing list