The DeepCool Assassin IV is the objective winner of this comparison, securing two out of three spec victories. While the Arctic Liquid Freezer III 420 holds a significant 25% advantage in TDP rating, the DeepCool Assassin IV provides a 10% improvement in noise level. This makes the latter the superior choice for users prioritizing acoustic performance over raw thermal capacity, as it maintains a quieter operation while still outperforming the former in the majority of measured specifications.

Choose the Arctic Liquid Freezer III 420 if your primary requirement is maximum thermal dissipation, as its superior TDP rating makes it the better option for handling high-heat loads. Conversely, select the DeepCool Assassin IV if you prefer a quieter computing environment. By offering a lower noise level and winning the majority of the evaluated categories, it serves as the more balanced and efficient solution for standard high-performance builds that do not require extreme cooling headroom.