Intel Core i9 12900 's Advantages
Released 2 years and 9 months late
Higher specification of memory (4800 vs 2666)
Larger memory bandwidth (76.8GB/s vs 41.6GB/s)
Newer PCIe version (5 vs 3.0)
Higher base frequency (2.4GHz vs 1.8GHz)
Larger L3 cache size (30MB vs 9MB)
More modern manufacturing process (10nm vs 14nm)
Intel Core i5 9400T 's Advantages
Integrated graphics card
Lower TDP (35W vs 65W)