Gamers Nexus kids did an "ipc" test.http://www.gamersnexus.net/guides/2977- ... clocks-ipc
Long story short: Vega FE performs pretty much identically to fury x at the same speeds. Any differences can more or less be attributed to the memory bandwidth and size.
There's really 2 ways to interpret this:
1. AMD straight up lied to everyone, there are no improvements, no geometry improvements, no rasterizer improvements, and on top of that they managed to make something worse than simply die shrinking fury x, that takes more die space and more power.
2. They just slapped the fury x drivers on Vega so none of the new features are being utilized.
Personally I think #2 is far more reasonable.
Looking at the professional benchmarks, the differences in drivers can triple the performance in some cases. Yeah, I think drivers make a difference.