GigaByte GTX 1080 TI Aorus vs Aorus Extreme and optimal tempaturee

Hello,

I was going to get the 1080 ti extreme, but i was told by the store owner that the Clock does not matter on mining.

is this correct? is any gtx 1080 will have the same hash rate as the others ?

Also, what is a good tempature to run the card in ? for example, right now im getting about 76c-77c - is that ok? or should i make better heat arrangements and have it down to ~65 ?

thanks !