Intel Core i5 6400 's Advantages
Integrated graphics card
Lower TDP (65W vs 140W)
Intel Core i9 7920X 's Advantages
Released 1 years and 11 months late
Higher specification of memory (2666 vs 2133)
Larger memory bandwidth (85GB/s vs 34.1GB/s)
Higher base frequency (2.9GHz vs 2.7GHz)
Larger L3 cache size (17MB vs 6MB)