Intel Core i5-8400 vs Intel Core i5-9400

The Intel Core i5-8400 (Coffee Lake S, Q4 2017) and the Intel Core i5-9400 (Coffee Lake S Refresh, Q1 2019) are Intel desktop processors for the mainstream market.

Both are manufactured using the 14 nm process and feature 6 cores and 6 threads. They utilize PCIe 3.0, have 9 MB of Level 3 Cache, 43 GB/s memory bandwidth, and an Intel UHD Graphics 630. In terms of performance, both CPUs show very similar performance. The Intel Core i5-9400 achieves a minimal advantage in single-core and multi-core applications due to slightly higher clock frequencies; however, the differences in benchmarks are less than 10 percent and are barely noticeable in practice.

For gaming, both provide a solid foundation with a dedicated graphics card, with the Intel Core i5-9400 potentially delivering marginally better results. Both CPUs have a Thermal Design Power (TDP) of 65 watts, indicating comparable power consumption and similar cooling requirements.

On the used market, the Intel Core i5-8400 is often more affordable and offers very good value for money. The Intel Core i5-9400 is slightly more expensive but does not offer a proportional performance increase. For price-conscious buyers, the Intel Core i5-8400 is the more recommendable choice for general use and gaming.

The Intel Core i5-9400 is an option if the price difference is minimal and marginal performance improvements are desired.