The Intel Core Ultra 5 250K Plus is the objective winner of this comparison, securing victory in ten out of fourteen measured specifications. While the Intel Core i5-9400F maintains a 59% advantage in Max Turbo Power, the Intel Core Ultra 5 250K Plus dominates the field with a massive 1900% improvement in L2 Cache capacity. This significant architectural lead makes the newer processor the superior choice across the vast majority of technical metrics provided.

Users prioritizing raw cache capacity for modern computing tasks should select the Intel Core Ultra 5 250K Plus to leverage its substantial L2 Cache advantage. Conversely, the Intel Core i5-9400F remains a viable option for those specifically seeking the power efficiency profile defined by its superior Max Turbo Power rating. Your decision should depend on whether your primary requirement is the expanded cache architecture of the newer model or the power specifications of the older unit.