I saw this today.
http://www.babeltechreviews.com/rx-v...game-showdown/
What's interesting is this summary from reddit:
Vega 56 is much faster the more recent games with a 11% difference on DX 11 alone between the 2013-2014 games and the 2016-2017 games when compared to the 1070 FE.Direct X 11 2013-2014 Games (2) - RX Vega 56 is 2.5% slower than GTX 1070 FE
Direct X 11 2015 Games (7) - RX Vega 56 is 1.6% faster than GTX 1070 FE (3.9%* faster GTX 1070 FE without the Fallout 4 HD -62.3% outlier)
Direct X 11 2016-17 Games (10) - RX Vega 56 is 8.5% faster than GTX 1070 FE
Vulkan Games (1) - RX Vega 56 is 21.9% faster than GTX 1070 FE
Direct X 12 Games (8) - RX Vega 56 is 13.8% faster than GTX 1070 FE
Total average (28 games - 3 or 4 resolutions) is RX Vega 56 is 8.1% faster GTX 1070 FE (8.7%* faster without the Fallout 4 HD -62.3% outlier)