The Phanteks G400A is the objective winner of this comparison, securing more category wins than the Corsair 4000D Airflow. The most impactful advantage offered by the Phanteks G400A is its included fan configuration, which provides a 100% improvement over the cooling hardware provided with the Corsair 4000D Airflow. This significant difference in out-of-the-box cooling equipment makes the Phanteks G400A the superior choice for users prioritizing immediate thermal performance without additional purchases.

Users who prefer a complete cooling solution should select the Phanteks G400A to take advantage of the doubled fan count included with the chassis. Conversely, the Corsair 4000D Airflow remains a viable option for builders who do not require the specific cooling hardware provided by the competitor. By choosing based on these hardware inclusions, buyers can ensure their selection aligns with their specific requirements for out-of-the-box component support and cooling capacity.