64 bit compatibility of MEROM, T7200, 2.0, 4MB

I have a D62 that is dying, or at least the motherboard is (if that is possible).  While research whether the chip was adequate for a NAS build I learned that the chip can handle 64 bit.  If the chip is capable can I just try and load a 64 bit OS or are the rest of the comonent needing to be compatible?  Also if you have any suggestions for motherboards for this chip that may let me play with a build of one form or another please let me know.