Maybe on average, but if you go into details, several games lose 8, 9 and 10% of performance. Heck Witcher 3 lost 14% @1080p. So it's very workload dependent, AMD wouldn't have pushed the clocks that high for a mere 4%. The least power saver is 200W in that review, which is still much higher than GP104 (166w), and with 10% less performance. You can push Pascal and Volta clock to the limits comfortably @~2.1GHz without increasing voltage or going through the roof in power consumption, so once more it comes down to architecture, which is what the main argument is about. One arc (Vega) has a ceiling on clocks and thus scales badly power wise once you push past a certain point, and the other one doesn't, because it has that certain threshold point at a much higher position. Even when it has nearly double the transistor count, and even when being on an older node. I've heard of several. Even unstable cards. Once more it's lottery.