Intel Core i5 6600 's Advantages
Integrated graphics card
Higher base frequency (3.3GHz vs 2.9GHz)
Intel Core i5 9400F 's Advantages
Released 3 years and 4 months late
Higher specification of memory (2666 vs 2133)
Larger memory bandwidth (41.6GB/s vs 34.1GB/s)
Larger L3 cache size (9MB vs 6MB)