The DeepCool Assassin IV is the objective winner of this comparison, securing two out of three spec victories. Its most significant advantage is a 27% higher TDP rating compared to the alternative, indicating superior thermal management capabilities for demanding hardware. While the DeepCool AK400 falls short in total spec wins, it maintains a distinct edge in value, offering an MSRP that is 70% better than the higher-end model.

Choose the DeepCool Assassin IV if your primary requirement is maximum thermal headroom for high-performance components. Conversely, the DeepCool AK400 is the logical selection for budget-conscious builders who prioritize cost efficiency over the increased TDP capacity provided by the larger cooler. Selecting between these two depends entirely on whether your build necessitates the superior thermal rating of the former or the significant MSRP advantage offered by the latter.