Intel Core i5 8400 's Advantages
Released 9 months late
Higher specification of memory (DDR4-2666 vs DDR4-2400)
Larger memory bandwidth (41.6GB/s vs 38.4GB/s)
Larger L3 cache size (9MB vs 8MB)
Intel Core i7 7700T 's Advantages
Better graphics card performance
Higher base frequency (2.9GHz vs 2.8GHz)
Lower TDP (35W vs 65W)