Thermal Performance
Overall, the thermal performance of the Phanteks Enthoo Pro II is impressive. A combination of high airflow due to the mesh front panel and support for multiple radiators means that even when both systems are under load, there is no sign of the CPU or GPU in both systems getting too hot, and there was only a slight increase of CPU temperature in both systems.
The only slight note of concern is the load temperature of the bottom graphics card. Being so close to the side panel means the bottom GPU does run a little hotter than what we would consider optimal, However, even with both systems under load, the temperature of the bottom card was still within acceptable limits.