Intel Core i9 12900H 's Advantages
Higher base frequency (2.5GHz vs 2.0GHz)
Intel Core Ultra 7 255H 's Advantages
Released 3 years late
Higher specification of memory (8400 vs 5200)
Newer PCIe version (5.0 vs 4.0)
More modern manufacturing process (3nm vs 10nm)
Lower TDP (28W vs 45W)