i guess the 1st question is...did you actually replace the motherboard with some random motherboard you found? ... or did it just randomly pop up and say this one day?
if it's the latter it could be bad drive in which case, Reload software, check security key is properly installed and the riser boards are properly plugged in (remove clean/reinstall).
if it's the former.... for obvious reasons, you can't just plotz a random motherboard into the system and expect it to work. the software is designed to work with a very select few makes/models of boards. (mitsubishi ITOX/telco 586/unicorn) and will not work with anything else.