Looks like you won the silicon lottery, good for you . Whats funny is my batch 2 came with the may firmware but wont overclock past 662 stable,  I can go for 668 but sometimes after 24-48 hours one of the boards drops off. I tried the fans at 100% and 750mhz but it crashes after a few min. Mine is stable at 662 55% fan setting. What I did was reverse the fan so that it pulls instead of blows and it dropped the temp by 10c and it runs at 50c.