Intel Core i9 13900K 's Advantages
Released 7 years late
Higher specification of memory (DDR5-5600 vs DDR4-2133)
Larger memory bandwidth (89.6GB/s vs 34.1GB/s)
Newer PCIe version (5.0 vs 3.0)
Higher base frequency (3.0GHz vs 2.7GHz)
Larger L3 cache size (36MB vs 6MB)
More modern manufacturing process (10nm vs 14nm)
Intel Core i5 6400 's Advantages
Lower TDP (65W vs 125W)