The Intel Core i5-9600K is the objective winner of this comparison, securing victory in six of the fourteen evaluated categories. Its most significant technical advantage over the Intel Core i5-6600K is its total core count, which represents a 50% improvement. While the older model maintains a 7% advantage in MSRP, the newer processor provides a substantial increase in core-based capabilities that outweighs the minor cost benefit of the predecessor.

Users prioritizing raw processing capacity should select the Intel Core i5-9600K to take advantage of its superior core count. This makes it the more capable choice for modern computing demands. Conversely, the Intel Core i5-6600K remains a viable option for budget-conscious buyers who prioritize the 7% MSRP advantage over the increased core count found in the newer model. Your choice depends on whether you value lower initial costs or higher core-based performance.