Intel Core i5 8259U Advantages
Higher base frequency (2.3GHz vs 2.0GHz)
Intel Core Ultra 7 255H Advantages
Released 6 years and 9 months late
Higher specification of memory (8400 vs 2400)
Newer PCIe version (5.0 vs 3.0)
Larger L3 cache size (24MB vs 6MB)
More modern manufacturing process (3nm vs 14nm)