PC modder der8auer built a 110-cm 3D-printed chimney to passively cool an AMD Ryzen 7 9800X3D CPU without using mechanical fans [1].
This experiment demonstrates that the "stack effect" can significantly lower hardware temperatures, potentially offering a path toward silent, fanless computing for high-performance processors.
The project utilized a 110-cm [1] structure printed from plastic to create a natural thermal draft. By leveraging the stack effect, the design allows hot air to rise and escape through the top of the chimney, drawing cooler air in from the bottom. This process removes heat from the processor without the need for powered cooling solutions [5].
Testing showed that the modification was effective in managing the thermal output of the Ryzen 7 9800X3D [3]. The chimney reduced the CPU temperature by approximately 19°C [2]. This reduction represents a substantial drop in heat for a system lacking active airflow.
The goal of the build was to show how radically simple physical modifications can influence thermal performance [1]. While traditional cooling relies on heat sinks and fans to push air across a surface, this method relies on the buoyancy of warm air to create a constant, natural flow [5].
Such a design is impractical for standard desktop cases due to its height and open nature. However, the results provide a benchmark for passive cooling efficiency in specialized environments where noise or mechanical failure must be avoided [4].
“The chimney reduced the CPU temperature by approximately 19°C”
While a 110-cm plastic tube is not a viable consumer product, the experiment validates the efficiency of passive convection for modern high-TDP processors. It suggests that if chassis design can be optimized for vertical airflow, the reliance on loud, energy-consuming fans could be reduced in industrial or enthusiast applications.
