Building a quiet PC is about more than choosing the right CPU cooler or a silent GPU—it starts with the airflow foundation inside your case. Case fans are the unsung heroes of a stable, cool, and whisper-quiet build. Yet the market is flooded with dozens of 120mm fans, all promising low noise and high airflow. The challenge isn’t just picking a “quiet” fan; it’s picking the right fan for the right purpose—airflow or static pressure—and matching it to your case layout.