Cooling Efficiency and Acoustic Performance
Prolimatech Megahalems Performance Tests
First of all, let’s check out the cooling efficiency of the new Prolimatech Megahalems solution depending on the rotation speed and number of fans. We used Scythe Slip Stream 120 fans at 500-1920RPM rotation speeds. They differ from other 120-mm fans by the rotor of smaller diameter and a strong airflow in the entire speed range. The fans were installed onto Prolimatech Megahalems cooler for intake and exhaust with the airflow directed towards the top of the system case:
We tested the efficiency of the new cooler in the following manner. First we determined maximum CPU overclocking with only one fan installed and working at 500RPM. Then we added a second fan with the same rotation speed, tested the CPU at the same frequency and then again determined the maximum overclocking but this time with two fans. The next step was to run the exact same tests with one fan rotating at 350RPM higher speed, and so on and so forth. The results are summed up on the diagram below:
The results show that the cooling efficiency of Prolimatech Megahalems cooler depends a lot on the fans rotation speed, up until the maximum speed. In other words, the claims of Prolimatech engineers about the Megahalems heatsink being optimized for fans with 800-1200RPM rotation speeds are not quite correct. With an additional fan installed for air exhaust or with the rotation speed of a single fan increased, we can see the CPU temperature go down by 4-7°C.
The overall CPU frequency gain that you get by switching from a single 500RPM fan to two fans at 1920RPM made +218MHz accompanied by the 7°C temperature drop on the hottest CPU core. However, if you take a closer look at the diagram, you will see that the most frequency increase occurs when we install two fans and raise their rotation speed to 860RPM. Further rotation speed increase doesn’t justify the significantly growing level of noise.