PC Unix help

[stephan.gross]

  I'm looking for suggestions by experienced PC-UNIX users.  My group is
undertaking a project to convert our monitor and control system (a special-
built diskless PC running OS-9) to a conventional PC.  I would greatly
appreciate any answers to any of the following questions:

  1) Recommended operating systems - I need multi-user, multi-tasking.
I guess the most recommended so far is SCO XENIX/UNIX.  I have heard of
others - ESIX, AIX, Interactive Architech.  How well do these perform?
How standard are they?  Any non-UNIX recommendations?  

  2) What are minimum system requirements for the operating system to
perform decently?  I'm guessing 2MB RAM, 40 MB hard disk.  Will increasing
these improve performance?  How much?

  3) Anyone with experience in data acquisition via PC?  Basically, I
need discrete input and output points.  Recommended manufacturers?

  4) Ditto the above with modem communications.  I know there are PC
cards containing 1 or 2 modems.  Can these things be driven via UNIX?

  Thanks in advance!


-- 

                               Steve Gross    (...att!homxc!sg)