The Intel Core i7-13700KF is the objective winner of this comparison, securing victory in ten out of fourteen measured specifications. Its most significant technical advantage over the Intel Core i5-8400 is its L2 cache, which is 1500% larger. While the Intel Core i5-8400 maintains a 74% advantage in Max Turbo Power, the superior cache capacity of the Intel Core i7-13700KF provides a more substantial lead across the majority of the evaluated hardware metrics.

Users prioritizing high-end technical specifications and the benefits of a significantly larger L2 cache should select the Intel Core i7-13700KF. Conversely, the Intel Core i5-8400 remains the appropriate choice for those who specifically require the power profile defined by its Max Turbo Power advantage. Your decision should depend on whether your primary requirement is the expanded cache architecture of the newer model or the specific power efficiency profile offered by the older processor.