Noctua NF-P12 Static Pressure Performance Page: 1

On the 5th of November, Austrian based cooling company Noctua released their highly anticipated NF-P12 120mm Fan. The NF-P12 shouldn't be considered as the successor to the NF-S12 merely because it promises better static pressure than what was seen from the NF-S12. The NF-P12 and NF-S12 are designed to compliment each other. Let's hear what Noctua had to say about the NF-P12:

The pressure-optimized Nine Blade Design of the NF-P12 (P stands for pressure, power and performance) has been specifically developed for high-impedance applications such as CPU coolers, water-cooling radiators, power supplies or cases with restrictive fan grills. It achieves outstanding static pressure and high airflow at very low noise levels.

While most conventional 120mm rotors possess seven comparably narrow fan blades, the NF-P12's Nine-Blade Design uses nine large, closely spaced blades with a relatively low angle of attack in order to achieve maximum static pressure and high airflow. As a result, the NF-P12 provides no less than 1.68 mm H2O at 1300 rpm, which is something that other fans merely achieve at 1600 rpm or more.

Now what we are about to conduct is a series of tests to see just how much static pressure the NF-P12 cooling fan will provide. This is not a full review, but should be considered as an addendum to the review conducted previously. Due to severe time constraints static pressure testing was not able to be conducted, nor included in the original review. If you would like to see the original review then head here

Noctua NF-P12 120mm cooling fan

Furthermore; the equipment that I have used for the static pressure testing phase of this review is not, and never will be equal to the testing facilities that Noctua employ. The static pressure results here should be taken as an indication, and I'd like to think of it as a pretty good indication, but once again professional testing laboratories win out over a kitchen table simulation every time.

For those of you interested in static pressure theory I have discussed it in some detail here

So without further delay let's get down to the nitty gritty and see how we're going to test the Noctua NF-P12 cooling fan...

Noctua NF-P12 Static Pressure Performance Page: 2
Testing Methodology

In order to accurately test the Noctua NF-P12 I have decided to review its performance from two perspectives:

* Static Pressure and air flow
* Cooling ability

The Noctua NF-P12 will be compared against the original NF-S12 (800 and 1200 RPM versions).

Static Pressure and Air Flow

In order to test the static pressure of the Noctua NF-P12 I constructed an air-tight test chamber which would allow me to physically assess how much additional static pressure the fan provided. The total approximate volume of the test chamber was 221.18 cubic inches. A digital Manometer was used to record the positive static pressure emitted by the fan. A Pito Tube from the digital Manometer was inserted into the test chamber out of the wind stream created by the fan, in order to prevent air velocity from corrupting the Manometer readings. Prior to testing the Digital Manometer was calibrated according to manufacturers specifications, in order to accurately read the resultant static pressure according to current atmospheric pressure.
Airtight shroud

Custom static pressure tester Pito tube for static pressure measurement
The NF-S12 and NF-P12 Fans were then forced to pass a volume of air through a Toyota Camry heater core, which will act as the radiator. The heater core has a fin count of approximately 84 fins/square inch and as such should provide more than enough resistance for validatable results. All static pressure readings were taken whilst the fans were running at 12v, and 3 x 60 second samplings were taken each time via RS232 software and uploaded to my computer via the serial port.

12v testing

#Note: The digital Manometer that I have used for todays testing is accurate to +/- 2%. However, the digital readout only records to 1 decimal place which makes the results relative in the grand scheme of things, but fails to provide an exact amount of static pressure i.e to two or more decimal places. Currently this is all my review budget allows for at the moment, but I will be upgrading my Manometer in the near future to a better model. So please bear in mind that when you see the static pressure graphs on the next page, that when a fan shows '0' static pressure it is actually between 0.0 cmH20 and 0.099 cmH20.

The NF-P12 and NF-S12 were tested for free air flow capacity using a calibratable digital Anemometer, upon which they were allowed to run at 5v, 7v and 12v respectively. I have chosen to test the fans at these three voltages due to the increasing number of people undervolting fans in the name of silence. Power for the testing phase was provided by a variable power supply, and the voltages checked using a digital test meter. The NF-P12 was also tested for air flow when installed on the airtight test chamber by using the calibratable digital Anemometer to record the air flow after it had passed through the cooling fins of the radiator.

Cooling ability

In order to assess the actual cooling performance of the Noctua NF-P12 I have set up a simple water-cooling loop comprising of the following items:

* Alphacool X2 Bold CPU Water Block
* Laing DDC Pro pump with OCLabs Top and 1/2" EK High-Tail barbs
* 1/2" XSPC clear tubing
* Intel E6600 CPU
* Variable Power Supply
* Digital volt meter
* Aerocool Gatewatch rheobus with digital display
* Toyota Camry heater core with custom made air tight tin shroud

Cooling test bench

I have set up two thermal probes on the inlet and outlet of the heater core and temperatures will be monitored on a digital rheobus so that we can see just how well the extra static pressure effects water temperature within the radiator. All fans will be run at 7v and 12v and the resultant temperatures recorded. CPU load will be obtained by running 1 x instance of Stress Prime 2004. Temperatures will not be recorded until they stabilise for each fan tested. Ambient temperature at the time of testing was between 26.8 and 26.9 Deg Celcius.

I have decided not to run with dedicated noise testing this time around due to time constraints, and that I wanted this review to be dedicated purely to assessing cooling performance. If the majority would like me to include dedicated noise testing then I will be happy to include it as an addendum.

Let's go testing....

Noctua NF-P12 Static Pressure Performance Page: 3
After running both the 800 and 1200 RPM versions of the Noctua NF-S12 120mm fans through our ghetto static pressure tester, we can see that they didn't fare very well. Please bear in mind that although the chart shows 0 cm/H2O of static pressure, it does in fact fall somewhere between 0 and 0.099 cm/H2O.
Noctua NF-S12 static pressure chart
Now this is looking better...the new Noctua NF-P12 shows a marked improvement in static pressure. Once again the static pressure shows 0.1 cm/H2O on our chart, but in reality would fall somewhere between 0.1 and 0.199 cm/H2O.
Noctua NF-P12 static pressure chart
We can see the increase in air flow of the Noctua NF-P12 over the older NF-S12 series.
Free air flow performance
And again once we try and measure the air flow through the radiator, the NF-P12 is the only fan that has enough static pressure to force the air through the radiator fins to register air flow on the Anemometer.
Radiator air flow
 Utilising both the NF-S12 and NF-P12 120mm fans on the radiator for our cooling tests yielded some interesting results. I have included some Scythe S-FLEX results in the chart to help make a comparison. The NF-S12 800 gets left behind at 7v, but the NF-P12 performs better than the Scythe S-FLEX's thanks to its increased static pressure. The NF-P12 certainly has the goods and it performs well whilst being almost totally quiet. Excellent effort Noctua!
Noctua NF-P12 vs NF-S12 Temperature Comparison
Voltage (v)7v7v12v12v
Radiator probe configInOutInOut
NF-P1233.4 DegC32.2 DegC31.6 DegC30.2 DegC
NF-S12 800
38.2 DegC36.2 DegC34.6 DegC33.2 DegC
S-Flex 80036.1 DegC35.7 Deg C33.6 DegC32.7 DegC
S-Flex 120033.4 Deg C32.9 DegC32.3 DegC31.2 Deg C
S-Flex 160033.3 DegC32.3 DegC31.8 DegC30.6 DegC
 Let's have a quick look over the page to see what we can summarise from this short performance review...

Noctua NF-P12 Static Pressure Performance Page: 4
Final Thoughts and Conclusion
So how well did the Noctua NF-P12 perform in todays testing?
The new Noctua NF-P12 now provides the static pressure needed for both heat exchanger and heat sink applications. All credit goes to Noctua for stepping up to the plate and making an even better product than the NF-S12's. Equally impressive is that you can now 'have your pie and eat it too' - cooling performance without the additional noise.
Subsequently, I have absolutely no hesitation in recommending the Noctua NF-P12 120mm cooling fans as a worthy addition to your cooling system.
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