Out of curiosity, I downclocked my CPU to 2GHz to see how viable Renoir silicon when downclocked to 2GHz or below would actually be, and this is how it turned out.

qt4 took longer to compile because, well, duh, lower clock speeds mean large packages take longer to compile, but being downclocked to 2GHz actually doesn't seem to hurt gaming much because this was actually kinda playable, although I sucked in this footage.

I'm probably going to bring the clock back up to 3.3GHz though as that's a happy medium clock speed. If I were just building an HTPC though, I wouldn't mind downclocking to 2GHz or lower because that would bring power consumption and thus heat output down to an absolute minimum; I don't even hit 20W under full load with a 2GHz downclock as shown here.