Look and see if there is an updated BIOS for your particular boards.
I have the same problem.
When I try to boot from USB (for installig xubuntu) I receive "BOOT ERROR".
I try ti update the bios at the last version MO0506P, but i receive the same error.
Yes, unbelievably, this board fails to boot from USB. There is a bug in the last three (!!!) BIOS versions (0400, 0501, 0506) which is being discussed in this thread:
Version 0506 was released recently (January 5) and did not fix the problem.