Intel Core i7-6700 vs Intel Core i5-8400

The Intel Core i7-6700, codenamed Skylake-S, is a 6th generation processor for desktop systems, designed for the mainstream to performance segment.

The Intel Core i5-8400, as part of the 8th generation under the codename Coffee Lake-S, also targeted the mainstream desktop market and brought an increased core count.

Both CPUs were manufactured by Intel using the 14 nm process and support PCIe 3.0. The Intel Core i7-6700 features 4 cores and 8 threads, while the Intel Core i5-8400 offers 6 physical cores and 6 threads. The Intel Core i7-6700 is equipped with 8 MB of L3 cache and achieves a maximum memory bandwidth of 34 GB/s.

The Intel Core i5-8400, on the other hand, has 9 MB of L3 cache and a maximum memory bandwidth of 43 GB/s. In terms of performance, the Intel Core i5-8400 shows a noticeable advantage in single-core tasks. Even in multi-core scenarios, the Intel Core i5-8400 generally demonstrates superior performance due to its higher number of physical cores, although a specific multi-core benchmark yielded comparable values.

For gaming scenarios, the Intel Core i5-8400 is the better choice due to its stronger single-core performance and increased core count, leading to a smoother gaming experience. The Intel Core i7-6700 features Intel HD Graphics 530, while the Intel Core i5-8400 has Intel UHD Graphics 630 as its integrated graphics unit.

Both processors have a Thermal Design Power (TDP) of 65 watts, indicating similar cooling requirements. As they are older generations, both CPUs are primarily available on the used market. Their price-performance ratio heavily depends on current market prices and the cost of the associated platform.

In summary, the Intel Core i5-8400 offers superior overall performance for most modern applications and games due to its more modern architecture and higher number of physical cores. The Intel Core i7-6700 can still be an option in systems with specific budget constraints or for older software that benefits from Hyper-Threading.