DDR4 is nothing special.
Finally, as far as DDR4 is concerned, the chips will top out DDR4-2133 and will only officially support DDR3-1600. If that’s true, it implies Intel is fudging configurations a bit to compensate for DDR4-2133′s higher latency — at the same clock speed, DDR3 is faster than DDR4 thanks to its intrinsically lower latency. DDR4 won’t pull ahead from DDR3 until it hits at least DDR4-2700 and I wouldn’t expect to see significant improvement until DDR4-3200. AVX3 should provide significant acceleration — AVX2 gave Intel chips a hefty kick over standard AVX — but its aimed at the same HPC markets where Xeon Phi has done well. The impact on consumer software may be minimal, at least in the near term.