The Intel Core i5-12600KF is the objective winner of this comparison, securing victories in ten out of fourteen measured specifications. Its most significant technical advantage is the L2 cache, which is 533% larger than that of the Intel Core i5-8400. This substantial increase in cache capacity provides the primary performance edge for the newer processor, establishing it as the superior option across the majority of the evaluated hardware metrics.

Users prioritizing high-performance computing should select the Intel Core i5-12600KF to leverage its vastly superior L2 cache capacity. Conversely, the Intel Core i5-8400 remains a viable choice for those specifically seeking a lower Max Turbo Power, as it holds a 57% advantage in that category. Choosing between these two components depends on whether your system requirements favor the expanded cache architecture of the newer model or the power efficiency profile of the older unit.