rolled back BIOS to BLH6710H.86A.0156.2012.0615.1908 ..
CMOS checksum errors gone ..
it appears BIOS after .0156 NOT ready for prime time for this DH67GD..
similar thread follows here:
hats off to Intel staff for keeping this thread hot /.d
Your feedback is important to us and I thank you for taking the time to communicate this issue.