The Intel Core Ultra 9 285K is the objective winner of this comparison, securing victories in eleven of the sixteen evaluated categories. Its most significant technical advantage is its L2 cache, which is 433% larger than that of the Intel Core i5-12400. While the latter component holds its own in three specific areas, the former demonstrates a clear superiority in the majority of the measured specifications, establishing it as the more robust option for high-performance computing requirements.

Users prioritizing maximum cache capacity and overall technical specifications should select the Intel Core Ultra 9 285K for their build. Conversely, the Intel Core i5-12400 remains the logical choice for budget-conscious buyers, as it offers a 67% advantage in MSRP. By choosing the i5-12400, consumers can capitalize on this significant cost efficiency, whereas the Ultra 9 285K is better suited for those who require the extensive performance benefits provided by its superior cache architecture.