The Phanteks NV5 is the objective winner of this comparison, securing victories in seven out of eight measured specifications. Its most significant advantage over the Lian Li A4-H2O is its maximum cooler height, which is 236% greater. While the Lian Li A4-H2O maintains a 7% advantage in MSRP, the Phanteks NV5 dominates the majority of the technical categories evaluated, making it the superior choice for users prioritizing hardware compatibility and cooling flexibility.

Users should select the Phanteks NV5 if they require substantial clearance for large cooling solutions, as its height capacity provides a clear functional edge. Conversely, the Lian Li A4-H2O is the appropriate choice for budget-conscious builders who prioritize a lower MSRP. By choosing based on these specific advantages, users can align their purchase with either the superior hardware support of the Phanteks NV5 or the cost efficiency offered by the Lian Li A4-H2O.