70 is a bit high, maybe windows is doing something in background. I have 50 right now and only browser open, my fans at 15% or so. For ECO, what PPT does Ryzen master show for you? 88 = ECO 65W, 142 or so = 105W (stock for 7700x)
What cooler do you have, is it mounted properly? how much boost do you get in cinebench or programs like that? Theoretically 95C under load is fine, after that boost will drop to not go over 95C. If you still get 5Ghz+ all core then maybe it is fine? (depending on cooler i guess)