The Intel Core i5-11400F is the objective winner of this comparison, securing a lead in eight out of fourteen measured specifications. Its most significant technical advantage is the thread count, which is 100% higher than that of the alternative. This substantial increase in processing capacity positions the Intel Core i5-11400F as the superior choice for users prioritizing multi-threaded performance and modern architectural efficiency over the specific power constraints found in the older model.

Users who require higher thread counts for their computing tasks should select the Intel Core i5-11400F to take advantage of its superior capacity. Conversely, the Intel Core i5-8400 remains a viable option for those who specifically prioritize a 58% advantage in Max Turbo Power. Choosing between these two processors depends on whether your primary requirement is the increased thread count offered by the newer model or the power profile provided by the Intel Core i5-8400.