62 is reasonable because the most Desktop's 3070s make 63 easily and some 64. Now 66 with 108W is completely out of reality and like you said it, there must be some kind of memory timings mod if that number is true. The way this user presents his results though... very fishy. I've seen before people like him selling viruses that "increase mining performance" through PMs in this forum.

It goes like this: someone asks how he does this speed, he PMs the person with a proposal and.... you know the rest.