MCA Micro-channel 
  10 MHz

  386SX : 24 bit address bus, 32 bit data.
  386DX, 486 : 32 bit address.

  Burst mode transfers.               
    (Think of fast page memory on a large scale.)

  Bus mastering by the interface cards.
    Cards could talk to each other without involvement of CPU.

  Type of Plug and Play - cards no longer needed jumpers. 
    But required a pair of software disks to configure.
      Reference disk (for particular system) to set the interfaces. 
     
      Options disk (for each card being plugged in) describing add-in device. 
        Which could be copied to reference disk.
 
  Different (smaller) interface layout. Not backwards compatible with ISA.

  IBM enforced its proprietary design with fees.
    (parts of the ISA architecture was also licensed, but no-one paid)

    Linux could not run on MCA bus system because of license conflicts.