>The crystal I have is a 20Mhz clock crystal from Jameco.  The
>schematic for the MIM only shows filtering caps from 5 volts to
>ground.  There's one for the MIM and another for its EEPROM.  both
>caps are 0.1 uF.

If you have a crystal, you need a pair of caps usually in about 20pF to ground.
It is possible that it was designed for a resonator with internal caps, in
that case there should be three leads for the "crystal".