Mostly from developer forums. The A12 has been estimated at 5-6w by reviewers who used power measuring techniques (e.g. Anandtech, etc running stress test bench

Mostly from developer forums. The A12 has been estimated at 5-6w by reviewers who used power measuring techniques (e.g. Anandtech, etc running stress test benchmarks). The A12Z on the Apple DTK has 2-extra CPU cores, and 3 extra GPU cores, so people have estimated based on scaling and clock, to be anywhere from 10w to 15w if you consider the device on plugged in power, running all cores, with clock boosting. Whether it's accurate or not, the reality is, the Ryzen Mobile is pretty efficient for its performance, and Intel LakeField is basically going with a "BIG.litte" architecture as well (x86+atom). AMD in particular is a fierce fighter, and they're not just going to sit still and let ARM capture the laptop and desktop markets, especially since a huge existing ecosystem gives them an advantage, and many people with work or business laptops aren't necessarily going to throw away everything to get an extra mm of thinness, or slightly longer battery life. After all, if battery life was the end all and be all, mobile phones could have doubled battery life a long time ago by simply doing less. Putting super high pixel density displays and constantly running background services is one reason why battery size keeps going up, but battery life hasn't improved as much.