Noctua NF-S12A FLX, ULN and PWM Case Fan Reviews

Test System

• Motherboard: ASUS P8Z77-V
• CPU: Intel Core i5 3570K  at Stock with Gelid GC Extreme Thermal Paste
• CPU Cooler: Cooler Master TPC 800 in Passive Mode (i.e. No Fans)
• RAM: 16GB Kingston HyperX 1866MHz DDR3
• GPU: XFX Radeon HD 5870 1GB
• Storage Options: 128GB Kingston SSDnow V100 (Boot Drive) and Samsung F3 1TB (storage)
• PSU: Antec High Current Gamer 620W
• Case: Cooler Master HAF 912

Testing Methodology

• Four of each fan type were fixed into the case in the same position. That is two in the front in-taking, one in the rear exhausting and one in the top exhausting.
• Delta temperatures have been used to account for small fluctuations in room temperature
• Prime 95 and Unigine Heaven were run for 10 minutes to stress the CPU and GPU respectively. The average maximum CPU, motherboard and GPU temperature(s) were recorded as noted by CPUID HW Monitor
• All other components of the test system were kept identical at consistent settings, only the case fans were changed.
• All fans were tested at 12 volts straight from the power supply with 12v volt molex adapters.
• The acoustic measurements were taken 10cm away from the tested fans with the power supply fan and GPU fan isolated/turned off
• The ambient noise level as recorded by our sound meter was 35.5 dBA and delta noise levels have been used in our graphs
• There is approximately a 1 degree celsius margin of error in our temperature recording software
• There is approximately a 1dBA margin of error with our decibel meter

Software Used

• CPUID HWMonitor
• Prime 95
• Unigine Heaven

Cooling Performance

Our results show the NF-S12A PWM and NF-S12A FLX posting identical results as they both have 1200RPM maximum rotation speeds. GPU temperatures were consistent across all fans suggesting that actively cooled hardware receives minimal benefit from the extra airflow. However, the temperature sensors on the motherboard and CPU, both of which were being passively cooled, varied a lot more. We can clearly see the benefit to the system of the more airflow.

For reference the SilverStone AP123 spin at 1500RPM, the Noctua NF-S12A PWM at 1200RPM, NF-S12A FLX at 1200RPM and NF-S12A ULN at 800RPM.

The Noctua 1200RPM fans (FLX and ULN) posted generally better scores than the SilverStone AP123 fans despite running at lower RPMs and being quieter. I think the results speak for themselves.

The acoustic performance below shows just how quiet the Noctua fans were. If you were after total silence then the ULN variety offers exactly that while the PWM and FLX versions offer much more performance with more noise. Arguably the NF-S12A PWM is going to vary depending the most on which speed you want, since it does anything between 300 and 1200RPM. That said the NF-S12A PWM is essentially the FLX and ULN models rolled into one providing you have the ability to control the fans via either a PWM header on your motherboard or through a fan controller.

Acoustic Performance