Alright it's definitely the speed that the motherboard can't handle. If both sets run at 667MHz perfect and then fail at higher speeds no doubt you have a faulty motherboard.
Alright then. I'll RMA the board after a new one arrives (as soon as I can order a new one.)
I want to thank you for all of your help. You have stuck with my issue for over a week now, and helped me out in more ways than you can imagine. I'm glad to finally have an answer.
Thank you for all of your time and patience. I didn't expect anyone to stick with me for this long. I am eternally grateful.