OK, then at this point I'd look into returning the motherboard. Can't be 100% certain that this is your faulty component, but to not beep when the RAM is removed would suggest that it is, in fact, DOA.
I'd consider returning it for a refund, if you can, and buying a quality alternative from ASUS.
"Take up our quarrel with the foe:
To you from failing hands we throw, The torch; be yours to hold it high.
If ye break faith with us who die, We shall not sleep,
though poppies grow, In Flanders fields." - John McCrae, May 1915