only if there is a price shift with the 700 series.
the 700 series is just a refresh of the 600 series... so a 770 will be a rebranded 680. a 760ti will be a rebranded 670... if say the 770 is priced at the 670 price point then yes. there will be a decrease in price. if those new boards are priced at the current prices for those 600 series prices or more (like a 770 priced at the 680 price), then no. there will be no price drop