The Intel Core i5-12400F is the objective winner of this comparison, securing a lead in seven of the fourteen evaluated specifications. Its most significant technical advantage is its L2 cache, which performs 200% better than that of the Intel Core i9-10900K. This substantial improvement in cache capacity provides the primary edge for the newer architecture, allowing it to outperform the older model across the majority of the measured categories.

Users prioritizing modern architecture and the efficiency of a superior L2 cache should select the Intel Core i5-12400F. Conversely, those who require a higher volume of processing units should choose the Intel Core i9-10900K, as it maintains a 67% advantage in total cores. Your decision should depend on whether your specific workload benefits more from the increased cache capacity of the former or the higher core count offered by the latter.