Intel Celeron J4005 's Advantages
Lower TDP (10W vs 65W)
Intel Core i5 8400 's Advantages
Better graphics card performance
Higher specification of memory (2666 vs 2400)
Larger memory bandwidth (41.6GB/s vs 35.76GB/s)
Newer PCIe version (3.0 vs 2.0)
Higher base frequency (2.8GHz vs 2.0GHz)