Yes it does fit! Well most of it. Noctua NH-D15 Phanteks P400a : r/Phanteks

Noctua NH-D15 Review

Buy Phanteks Eclipse P500A Airflow D-RGB Tempered Glass Black [PH-EC500ATG_DBK01]

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Showing some love for the P400A : r/Phanteks

Air cooler for Ryzen 5800X

Buy Phanteks Eclipse P500A Airflow D-RGB Tempered Glass Black [PH-EC500ATG_DBK01]

Looking for the best 120mm AIO (8700k / 9700k) - Custom Loop and Exotic Cooling - Linus Tech Tips

ASUS ROG Crosshair X670E Overclocking & Discussion Thread

Biggest cooler that fits in the P400A? - Cooling - Level1Techs Forums

Does Noctua NH-D15 fit Phanteks Eclipse P400S? - Cooling - Linus Tech Tips

Biggest cooler that fits in the P400A? - Cooling - Level1Techs Forums

My new case hasn't turned up yet and I just couldn't let a Arctic Liquid Freezer 2 420 sit in the box. : r/overclocking

Fractal Design Pop XL Air RGB Black Tempered Glass Clear Tint : Electronics

Noctua NH-D15S Dual Radiator Intel/AMD CPU Cooler LN65214

X58 overclocking club