Intel Core i9 10900X 's Advantages
Larger memory bandwidth (93.8GB/s vs 76.8GB/s)
Higher base frequency (3.7GHz vs 2.5GHz)
Larger L3 cache size (20MB vs 18MB)
Intel Core i5 12400 's Advantages
Released 2 years and 3 months late
Integrated graphics card
Higher specification of memory (4800 vs 2933)
Newer PCIe version (5.0 vs 3.0)
More modern manufacturing process (10nm vs 14nm)
Lower TDP (65W vs 165W)