The Thermalright Peerless Assassin 120 is the objective winner of this comparison, securing victories in two out of three evaluated specifications. While the Noctua NH-U12A offers a notable advantage in acoustics, providing a 12% improvement in noise level, the Thermalright Peerless Assassin 120 holds the most significant edge in this matchup. Its primary strength is its MSRP, which is 64% better than that of its competitor, making it the superior choice regarding cost efficiency.

Users prioritizing budget-conscious builds should select the Thermalright Peerless Assassin 120 to capitalize on its substantial MSRP advantage. Conversely, those who place a premium on a quieter computing environment should opt for the Noctua NH-U12A. By choosing the latter, you gain the benefit of its superior noise level performance, which remains its most impactful advantage over the alternative. Your final decision should depend on whether you value lower acquisition costs or reduced operational sound.