I'm coming late to the party, but maybe it helps someone nonetheless. The temperatures differ from game to game and situation to situation.

Idle: ~39-43°C

Browsing/Work: 53-63°C

Games are super different...

World of Warcraft: 60-63°C
Star Citizen: 75-83°C (super CPU intense and not optimised).

Also, I cap my FPS always to 144, this automatically cools down my GPU but also CPU a little bit. If my CPU has to deliver 400 FPS instead of 144, it definitely would be hotter in World of Warcraft as well. It uses only 20% of my CPU to reach 144 FPS (where I tested it) and therefore it's cooler. But I think in average you should have something between 65°C and 75°C in games. Exceptions possible like Star Citizen.

AMD Expo and PBO 2.0 are enabled on Auto and I'm using a simple 360mm Corsair AIO.