Intel Core i5 8400 's Advantages
Higher base frequency (2.8GHz vs 1.1GHz)
Larger L3 cache size (9MB vs 4MB)
Intel Core i3 1000NG4 's Advantages
Released 2 years and 5 months late
Higher specification of memory (LPDDR4-3733 vs DDR4-2666)
Larger memory bandwidth (58.3GB/s vs 41.6GB/s)
More modern manufacturing process (10nm vs 14nm)
Lower TDP (9W vs 65W)