Need Recommendations On 386/486 UNIX systems

[Neal Rauhauser -- ELT Computer Applications Group]

     I have $10k budgeted to build a system to handle 10 - 15 concurrent
users. There will be 8 - 16 serial ports and a 1.5 MHz T1 line. Users
will be running a news reader and downloading information, not much else
will be occuring on the system. I'm not the least bit scared of PC
hardware but my only unix admin experience has been on my 'mighty
but erratic' coherent/286 system and a LMI Lambda - toy unix in both
cases. I need suggestions on the following:

    1. processor speed, 386 or 486, cache sizes?
    2. system ram, 12 meg? 16 meg? more?
    3. disk controller? Adaptec 1740? 
    4. 16 port serial card?
    5. the best worm or MO disk with worm capabilities - necessary for
       legal/archive purposes
    

    The most importatn question in my mind is what processor/speed
  and how much memory I should use. Mail replies and I'll post a
  summary.

   Neal  i1neal at exnet.iastate.edu