Intel Core i3 7100U 's Advantages
Better graphics card performance
Lower TDP (15W vs 45W)
Intel Core i5 9400H 's Advantages
Released 2 years and 8 months late
Higher specification of memory (2666 vs 2133)
Larger memory bandwidth (41.8GB/s vs 34.1GB/s)
Higher base frequency (2.5GHz vs 2.4GHz)
Larger L3 cache size (8MB vs 3MB)