The AMD Ryzen 9 9900X is the objective winner of this comparison, securing victories in ten out of fourteen measured specifications. Its most significant technical advantage is the L2 cache, which is 700% larger than that of the Intel Core i7-8700K. This substantial increase in cache capacity provides the primary performance edge for the newer processor, establishing it as the superior choice across the majority of the evaluated hardware metrics.

Users prioritizing modern architecture and high-capacity cache should select the AMD Ryzen 9 9900X for their next build. Conversely, the Intel Core i7-8700K remains a viable option for those specifically seeking a lower Max Turbo Power, where it holds a 41% advantage over the competitor. Choosing between these two components depends on whether your workflow benefits more from the expanded cache of the Ryzen or the specific power profile of the Intel processor.