Intel Core i7 6700K 's Advantages
Integrated graphics card
Higher base frequency (4.0GHz vs 3.2GHz)
Lower TDP (91W vs 140W)
Intel Core i7 6900K 's Advantages
Released 9 months late
Higher specification of memory (2133 vs 2133)
Larger memory bandwidth (76.8GB/s vs 34.1GB/s)
Larger L3 cache size (20MB vs 8MB)