UNIX compatible 386 motherboards ?

[John Mcleod]

I am considering upgrading my box with a 386 motherboard to run UNIX - 
probably ESIX, but I am worried about compatibility issues. Do my concerns
in this area have foundation ? If so, how can I tell if motherboard x will
enable me to run UNIX ? Is the compatibility issue confined to the
motherboard, or does it extend to the i/o boards ?
   Comments, suggestions or knowledge would be appreciated....

- John Mcleod