Well, ladies and gentleman, it’s here! The highly anticipated completely passive CPU cooler from Noctua, the NH-P1.

This is a project they they have been teasing for a while now and as you would expect from Noctua, this is a product that has been developed from the ground up specifically to be used in an entirely passive scenario via natural convection. ‘Why?’ you ask. Can you imagine, no noise output in full load with a high end CPU? That’s what it promises.

Alongside it, Noctua is offering also an ultra low noise / low RPM premium 120mm fan for the P1, just in case you want an even more capable semi-passive setup. The new fan is called the NF-A12x25 LS-PWM which uses the in-house made Sterrox® liquid-crystal polymer material, reference-class SSO2 bearing, comes with a rich bundle of accessories and has 6-year manufacturer’s warranty. All of this means you get one of the best 120mm fans that they currently offer.

Despite any initial scepticism you might have when we hear statements like ‘completely passive cooling with a high end CPU’, this P1 beggars belief since Noctua would have never released anything of this calibre without any due diligence.



Established in 2005, Noctua took international silent enthusiasts’ hearts by storm and quickly developed into one of the most acclaimed suppliers of premium quality quiet cooling products. Today, Noctua is present in more than 30 countries across the globe and working with several hundred sales partners. Chosen by noise-conscious PC users, system integrators and industry clients alike, Noctua has become synonymous with impeccable quality, excellent customer service and class-leading quiet cooling performance.

Designed in Austria, Noctua’s premium cooling components are internationally renowned for their superb quietness, exceptional performance and thoroughgoing quality. Having received more than 6000 awards and recommendations from leading hardware websites and magazines, Noctua’s fans and heatsinks are serving hundreds of thousands of satisfied customers around the globe.


Prices and Availability


The NH-P1 is priced accordingly given its highly specialized and niche nature. You might raise the question that if you get the extra fan as well, for far less dinero you can get a D15(S) for example. However, we must remember that a completely passive CPU cooler, is a different prospect.

*24.07.21 Update – Here’s the video review as well!*


Presentation and Specifications


* Courtesy of their website.


Visual Inspection


Both the NH-P1 and NF-A12x25 LS-PWM fan come shipped in the instantly recognizable Noctua themed livery.

On the front we have the main highlights of the products.

Noctua always presents the specs, scope of delivery and the main features in great detail.

The A12x25 LS-PWM fan has this top flap cover and when opened we get further information via a lovely graph regarding the exact purpose of this particular new fan model.

The same presentation continues inside as per any big Noctua CPU cooler, where we are greeted by the accessory box that has a visual inventory list printed on the front.

I invite you to spot something new regarding the P1’s accessories.

SecuFirm2+™ multi-socket mounting system (Torx)
1x NT-H2 high-grade thermal compound
1x NA-CW1 cleaning wipe
3x Installation manuals
2x Fan clips for optional 120mm fan
1x Noctua Metal Case-Badge

We have a full sized Torx! screwdriver called the NM-SD1. This is for the updated Torx securing screws.

Moving onto the fan which is nested inside this transparent plastic tray with the accessories located in their own cutout.

The A12x25 LS-PWM comes with:

1x NA-RC8 Low-Noise Adaptor (L.N.A)
1x NA-YC1 4-pin PWM y-cable
1x NA-EC1 30cm extension cable
4x NA-AV2 anti-vibration mounts
1x NA-AVG1 anti-vibration gasket for water cooling radiators
4x Fan screws

Now let’s release the Kraken ! Behold the 1180g cube of basically layered metal. It measures 158 (H) x 154 (W) x 152 (D) and is made of the Noctua ‘classic’ combo of copper (for the base and heat-pipes) and aluminium (for cooling fins) whith soldered joints & nickel plating.

As you can imagine, for this to dissipate that amount of heat, it needs to a have a big heatsink. Hence why the P1 has such an imposing presence. It uses 13 properly thick fins at 1.5 mm each with extra air vents on all of them. Those round numbered holes are for the placement of the fan’s metal securing clips.

It uses 6 copper nickel plated heatpipes that are beautifully crafted and offset throughout the cooling fins.

The same heatpipes join into the contact plate that is also made of copper with nickel plating and has an almost mirror polish. Nevertheless, the overall machining is just wonderful.

The fins are intertwined with each other with ample spacing, a fact that we are not usually accustomed to see in regular heatsinks. This is on purpose of course, to further help the passive cooling.

The P1 can be mounted in two orientations for the AM4 socket and if you have to install it with the side that will cover the RAM area, then you have around 40 mm to play with.

Now for the fan, which as per the regular NF-A12x25 one, is their most advanced 120mm fan to date. It has all the hallmarks that we know from Noctua, with the main difference here is the lower RPM and calibration. It will spin up to 1200 RPM, push 55,7 m³/h with a static pressure of 0,82 mm H₂O while not going over 12,1 dB(A) of sound.

It features the amazing magnetic oil-based hydrodynamic bearings rotor technology called the SSO2. Then the blades have metal reinforcements and flow acceleration channels in order to lower vortex noise and achieve higher airflow efficiency.

Since Noctua builds their product with incredible quality control and thus tight tolerances, the blades sit at just 0.5mm from the frame (most fans are over 2mm and above). When they spin, there is a challenge to overcome called impeller creep which basically means that the blades may touch the frame due to stretching. To overcome this Noctua development a new material called Sterrox which is a novel liquid-crystal polymer (LCP) type material that has much better dimensional stability and less creep as compared to conventional engineering thermoplastics such as ABS, PA, PBT or PC.




If you ever installed and handled a massive CPU cooler, this will be the same. Noctua only recommends that you install the P1 in an enclosure with good natural convection and they even published a PC case list. They also recommend that you go the standard ATX route for your motherboard.

The overall installation process is very easy thanks to their SecureFirm2+ system and since we are using the AM4 socket, this will be a breeze. The first step is to remove the stock AMD front plastic brackets and retain the backplate. Then attach the grey AM4 spacers.

Start to secure the metal AMD brackets while making sure that they are facing inwards the CPU.

This is where you need to use the new Torx screwdriver. They went this route because higher torque to be exerted than a similarly sized conventional hex socket head without damaging the head and/or the tool.

Apply the thermal paste and then install the P1. Since the fins are so spread apart, there is plenty of access.

On the AM4 socket you can only place it two directions. In our case it cleared the VRM heatsinks and thus there is no limit on what RAM to install.

There are no issues on the PCIe area as you can see.

Regarding the VRM area and motherboard heatsinks, again everything clears perfectly and this particular motherboard has some tall architecture around the socket area.

As for the fan, you can attach it either on the top or on the side of the P1 via the metal wire clips in the designated holes. Again, this fan is a separate ‘upgrade’ and it doesn’t come with the P1.


Testing methodology


  • The AMD Ryzen 7 1700 CPU will be tested at stock settings and then overclocked at 3.70 GHz for 1.325v
  • As the main torture test, we will employ a 2 minute run in AIDA64
  • Room temperature was recorded at ~ 20°C
  • For the noise testing, we used our Pyle PSPL01 placed 30 cm away from the setup – all other fans will will be off or set at minimum RPM
  • Thermal paste used – Noctua NH-H2
  • We will compare the results to other CPU air coolers close to its price/performance bracket
  • All CPU fans will be left on the ‘standard’ auto % rpm curve to simulate real life usage patterns and the side panel is now attached and the case fans are set at a fixed 30% RPM
  • The tests for the A12x25 LS-PWM being mounted on the P1 will be done just for the OC scenario
  • Any results over 90° C in any condition are considered a fail

Competition CPU Coolers:

Noctua NH-U14S140 mm
Noctua NH-D15 chromax.blackDual 140 mm
Noctua NH-U12ADual 120 mm
SilverStone IceGem 360 mm AIO Triple 120 mm
SilverStone Hydrogon D120 ARGB Double 120 mm
Noctua NH-D9L92 mm
AMD Wraith Spire RGB92 mm

Hardware used:

CPU: AMD Ryzen 7 1700 AM4 – 8c/16t @ 65W TDP
RAM 16GB DDR4 T-Force Night Hawk RGB 3000 MHz CL16
Motherboard: ASUS ROG STRIX X370-F Gaming ATX @ BIOS 5220
Boot SSD: ADATA XPG SX6000 128GB TLC M.2 NVMe 1.1 Gen3 x4
Video card(s): KF2 GTX 480 Anarchy Accelero Xtreme Plus
PSU: bequiet! 550W Pure Power 11 FM Gold
Case: bequiet! Silent Base 802 Black
Case fans: 3x bequiet! Pure Wings 2 140 mm


OS: Windows 10 Pro x64 21H1
GPU Drivers: NVIDIA GeForce WHQL 391.35
Core Temp v1.17 – To see the temperatures in real time
CPU-Z v1.95 – To verify the CPU’s statistics
AIDA64 Extreme v6.23 – Another popular total system stability test
Cinebench R15 – Popular CPU benchmark
Cinebench R20 – The new revised version optimised for the newer multi-core CPUs
MSI Afterburner v4.62 – To record the FPS and load/temperatures

Resolution for our test game Rise Of the Tomb Raider, is set at 1920×1080 with everything at Medium quality settings and no AA.

To point out that some motherboards may not boot if they detect that there is no fan plugged in the CPU_FAN header. Thus just select ‘Ignore’ in your bios in order to proceed.


Testing, Results and Analysis


Let’s start in order of CPU load difficulty. First up is the Cinebench R15 test. On the left we have the CPU in stock form while in the middle we have it overclocked. The third picture has the OC scenario with the NF-A12x25 LS -PWM fan attached as intake.

Despite the fact that the P1 isn’t meant to be used in an overclocked scenario, these are impressive numbers!

The Cinebench R20 is a more modern up to date multi core benchmark suite. So naturally we will see a bigger load and thus a larger temperature figure than the R15.

This is a more demanding test and things are even clearer now and the P1 still hasn’t made the CPU even in the overclocked scenario to thermal throttle.

In AIDA64 we isolated the stress test just for the CPU therefore we should get the highest stress scenario for the CPU but sometimes we get mixed results where the R20 will push the CPU further than AIDA in terms of heat output.

Here we have another reshuffling in the ranks and finally the passive setup is almost showing its limits in the OC scenario.

Rise Of the Tomb Raider is a fantastic game and also a good testing title for both GPUs and CPUs. Still not as stressful as a synthetic torture test but a great indicator of real life usage. Since the game isn’t pushing the CPU as much as a synthetic benchmark, we get really good results.

As you can imagine, because it survived the unofficially recommended OC scenarios and torture stress test, then it’s obvious that it will handle (most) gaming scenarios.

This will be a first since there is no noise testing to perform with the NH-P1. Even more so with the A12x25 LS-PWM fan because this thing is so silent even at 100% that it’s ridiculous and even the sound meter was picking up the noise mostly from the ambient and from the other fans in the case, which all were running at minimum RPM.




This is a tricky one to gauge. Are you after the best passive/fanless CPU cooler money can buy at the moment of this writing? Then the P1 is just that. Noctua just out-builds and out-engineers most companies and the P1 is no exception. But is it worth it though? That boils down to the consumers if they are after such a niche product because it has too much competition when it comes to the asking price and not to mention if you are after the fan upgrade as well. We think this is the P1’s biggest challenge that it has to overcome: itself. This is because it’s just too special for the time being. Alas, it fully works and thus it sets a precedent because now we have the option to go this path and know that it’s a damn viable approach.

The good:

+ Exceptional overbuild quality
+ The passive design really works
+ Completely ‘dead silent’ builds are now viable
+ Easy to install despite its massive size
+ 6 years warranty

The bad:

– Pricey especially when compared to any of their top tier CPU coolers at this price levels
– Massive thus you need to be certain of your end build especially if you get the extra fan

Glob3trotters “Unique” Award – 4.5 out of 5


Many thanks to Noctua for supplying us with these samples !


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