AFAIK, all the fanless EPIA-M/CL/MII/TC use the VIA Eden core...
This page for the EPIA-M (the same is true for all the other EPIAs mentioned above) states that "Processor - VIA C3/EDEN EBGA Processor" and therefore I believe that the 10000 boards have Nehemiah cores while the fanless version use the Eden core.