Since today's BIOS update apparently fixed the crashing issues which plagued this board when any downlocking occurred, I was able to see exactly how efficient Ryzen was under idle. While it doesn't drop lower than 2200mhz, the voltage drops to 0.8v, and as a result power consumption drops to 0.4w. Now, this isn't a huge deal on desktops of course, but with Ryzen and Vega based (Raven Ridge) APU laptops due out before much longer, it should achieve great battery life, since laptop chips should be able to drop even lower than this, and of course laptop chips won't be 8C/16T units. This is a long way from that A4 dual core 1ghz chip AMD sold for the tablet market (which were realllllllllllllllllllllllllllllllllllllllllllllllllllllllllllly slow, as I can testify to.)
Of course being a desktop chip, it really sucks down the power under stress, but this is beside the point.