The three biggest factors that affect CPU cooling performance are radiator surface area, airflow, and ambient temperature. Will the combination of good case airflow and thicker radiators mitigate the effect of a closed system on air cooling performance?
The thickest cooler in today’s comparison, Rosewill’s FORT120 leads even though its fan must use warmer case air, rather than outside air, to cool the sink. Reversing the fans to mimic the Corsair H50 orientation helped bring down CPU temperatures slightly, but only at idle. Looking more closely at the second-place tie, the H50 was only able to match the mid-thickness True Spirit in performance when both were configured with Rosewill’s faster fan.
Reversing the exhaust fan as per Corsair’s H50 installation instructions has a significant impact on internal air temperature, increasing its rise over ambient by more than 100% compared to the original fan configuration.
Northbridge temperature isn’t as severely impacted by having the exhaust fan serve as an intake, although the three configurations with the reversed fans still finish last.