The NH-L9a-AM4 chromax.black is an all-black version of Noctua’s award-winning NH-L9a-AM4 low-profile quiet CPU cooler for AMD Ryzen based HTPCs and Small Form Factor (SFF) builds. Thanks to the same proven heatsink design and NF-A9x14 PWM fan, it stays true to the NH-L9a-AM4’s successful formula of fusing a height of only 37mm with strong performance and excellent quietness of operation, as well as 100% RAM and PCIe compatibility. At the same time, the chromax.black version with its black fan and black coated heatsink combines these assets with a sleek stealth look. Topped off with the renowned SecuFirm2™ low-profile mounting system for AMD AM4, Noctua’s enthusiast-grade NT-H1 thermal compound and a full 6-year manufacturer’s warranty, the NH-L9a-AM4 chromax.black is a premium choice for customers who seek an ultra-compact heatsink that looks just as great as it cools.

The NH-L9a-AM4 is a highly compact, quiet low-profile cooler designed for use in small form factor cases and HTPC environments. While it provides first-rate performance in its class, it is not suitable for overclocking and or CPUs that create high heat loads. Please consult our CPU compatibility list to find out whether the NH-L9a-AM4 is recommended for your CPU/APU.
Award-winning NH-L9a-AM4 cooler

Award-winning NH-L9a-AM4 cooler

Tens of thousands of enthusiast users all over the world swear by the NH-L9a-AM4’s quality and performance. Recommended by more than 50 international hardware websites and magazines, it is renowned as being one of the best low-profile coolers for AMD Ryzen CPUs and APUs.
chromax.black design

chromax.black design

The NH-L9a-AM4 chromax.black is black from head to toe: Featuring a black coated heatsink, a black fan with black anti-vibration pads, black fan screws and black mounting parts, it’s right at home in all-black builds and easy to integrate with other colour schemes.
37mm low profile

37mm low profile

Due to the slim 23mm heatsink and the NF-A9x14 low profile fan that measures only 14mm in thickness, the NH-L9 stands a mere 37mm tall, which makes it ideal for use in compact HTPCs or Small Form Factor cases that offer minimum clearance for CPU coolers.
100% RAM compatibility

100% RAM compatibility

The NH-L9a-AM4 has a compact footprint that fully complies with the socket keep-out zones specified by AMD. This means that neither the heatsink nor the fan overhang the RAM, so the cooler provides easy access to the slots and is fully compatible with tall memory modules.
100% compatibility with PCIe cards on mini-ITX

100% compatibility with PCIe cards on mini-ITX

Some AMD-based mini-ITX motherboards have the PCIe slot located close to the CPU socket zone. While larger coolers that exceed this zone may block the PCIe slot, the compact-sized NH-L9a-AM4 provides full compatibility with PCIe cards.
Easy access to near-socket connectors

Easy access to near-socket connectors

Many low-profile coolers use larger fans or heatsinks in order to achieve sufficient performance, but by protruding over the socket zone, they make it difficult or even impossible to reach near-socket connectors on tightly packed ITX motherboards. Thanks to its compact footprint, the NH-L9a-AM4 provides easy access to all connectors and components.
NF-A9x14 PWM premium fan

NF-A9x14 PWM premium fan

The highly optimised, award-winning NF-A9x14 premium fan features Noctua's proprietary AAO frame as well as sophisticated aerodynamic design measures. Supporting PWM for fully automatic speed control, the NF-A9x14 allows the NH-L9a-AM4 to stay remarkably quiet.
Low-Noise Adaptor

Low-Noise Adaptor

Allowing the maximum speed of the NF-A9x14 PWM fan to be reduced from 2500 to 1800rpm, the included Low-Noise Adaptor (LNA) makes it possible to achieve near-silent setups with suitable CPUs/APUs that only create smaller heat loads.
Custom-designed SecuFirm2™ mounting for AM4

Custom-designed SecuFirm2™ mounting for AM4

The NH-L9a-AM4 comes with a custom-designed SecuFirm2™ mounting system for the AM4 socket of AMD’s Ryzen platform. Allowing the heatsink to be fixed from the back of the motherboard, it makes installation easier than ever, all while maintaining the trusted SecuFirm2™ quality.
NT-H1 thermal compound

NT-H1 thermal compound

Noctua’s much-acclaimed NT-H1 is a pro-grade TIM solution that provides minimum thermal resistance, excellent ease of use and outstanding reliability. Chosen again and again by overclockers and enthusiast users worldwide, it has established itself as a benchmark for premium-quality thermal compounds.
Soldered interface between heatpipes and fins

Soldered interface between heatpipes and fins

With many heatsinks, the fins are press-fitted to the heatpipes. Due to the different thermal expansion coefficients of copper and aluminium, this fit can loosen over years of thermal cycling, which may lead to reduced performance. By contrast, the NH-L9a’s fins are soldered to the heatpipes in order to guarantee a superior thermal interface that doesn’t deteriorate even after many years of usage.
6-year manufacturer’s warranty

6-year manufacturer’s warranty

Noctua products are renowned for their impeccable quality and outstanding longevity. Like all Noctua fans, the supplied NF-A9x14 features an MTTF rating of more than 150.000 hours and the entire NH-L9a package comes with a full 6-year manufacturer's warranty.
NH-L9a-AM4 chromax.black
Notes and warnings
The NH-L9a-AM4 is a highly compact, quiet low-profile cooler designed for use in small form factor cases and HTPC environments. While it provides first-rate performance in its class, it is not suitable for overclocking and or CPUs that create high heat loads. Please consult our CPU compatibility list to find out whether the NH-L9a-AM4 is recommended for your CPU/APU.
Cooler Specification
Height (without fan)
23 mm
Width (without fan)
114 mm
Depth (without fan)
92 mm
Weight (without fan)
390 g
Height (with fan)
37 mm
Width (with fan)
114 mm
Depth (with fan)
92 mm
Weight (with fan)
465 g
Copper (base and heat-pipes), aluminium (cooling fins), soldered joints & nickel plating
Max. TDP
Fan compatibility
92x92x14mm, 92x92x25mm
Scope of delivery
  • Black NH-L9a-AM4 heatsink
  • NF-A9x14 HS-PWM chromax.black premium fan
  • NA-RC7 Low-Noise Adaptor (L.N.A.)
  • NT-H1 high-grade thermal compound
  • Black SecuFirm2™ AM4 mounting kit
  • Black Screws for 92x92x25mm fans
  • Noctua Metal Case-Badge
6 Years
FAN Specification
Noctua NF-A9x14 HS-PWM chromax.black
Max. rotational speed (+/- 10%)
2500 RPM
Max. rotational speed with L.N.A. (+/- 10%)
1800 RPM
Min. rotational speed (PWM, +/-20%)
600 RPM
Max. acoustical noise
23,6 dB(A)
Max. acoustical noise with L.N.A.
14,8 dB(A)
Input power
2,52 W
Voltage range
12 V
> 150.000 h
NH-L9a-AM4 chromax.black
17.02.2020 // PCEkspert.com

NH-L9a-AM4 chromax.black Review

Testni se stroj bazirao na ASRockovoj X570 Phantom Gaming X ploči na kojoj je bio Ryzen 3400G. Testirali smo zagrijavanje procesora uz pomoć OCCT-a (medium data set), a temperaturu smo očitali nakon sat vremena opterećenja u HWInfo64 aplikaciji. Kao što vidimo na grafu, hladnjak smo usporedili s Wraith Spire hladnjakom koji AMD daje uz procesor. Samo za usporedbu, Wraith Spire je visok oko 50 milimetara čime nadvisuje memorijske module, dok je L9a-AM4 niži od njih. Vidimo da je i Noctuin hladnjak nešto moćniji i bolje hladi 3400G, a Wraith Spire je nešto malo i bučniji – 44 vs. 43,5 dB(A), unatoč činjenici da mu je ventilator nešto sporiji na maksimumu 1.870 vs. 2.560 RPM.
Test verdict: "Kao što smo iz testa vidjeli, L9a-AM4 je odlična zamjena za BOX hladnjake koji dolaze uz Ryzene. Malo je tiši (iako zapravo čujan), ima niži profil i bolje hladi procesor kao što je Ryzen 3400G." (Krešimir Matanović, PCEkspert.com)
11.02.2020 // HWready.it

NH-L9a-AM4 chromax.black Review

A nostro parere investire su un dissipatore veramente ultra compatto, che abbia ottime performance per la sua taglia e soprattutto che lavori in silenzio è sicuramente un ottimo investimento. La qualità dei materiali, l’ottimo bundle e le performance giustificano ampiamente il prezzo.
Test verdict: "A nostro parere investire su un dissipatore veramente ultra compatto, che abbia ottime performance per la sua taglia e soprattutto che lavori in silenzio è sicuramente un ottimo investimento. La qualità dei materiali, l’ottimo bundle e le performance giustificano ampiamente il prezzo." (Mauro Santoro, HWready.it)
10.02.2020 // PC-Gaming.it

NH-L9a-AM4 chromax.black Review

Noctua NH-L9a-AM4 Chromax impressiona come prestazioni e riesce ad essere tra i più compatti e silenziosi sul mercato. Come sempre la qualità e l’offerta è ottima, ma il prezzo di 49,90 euro potrebbe essere un po’ elevato considerando anche la limitata compatibilità.La versione Chromax offre una colorazione completamente nera sostituendo i classici colori Noctua, esteticamente è minimale e si adatta facilmente a qualsiasi PC.
Test verdict: "Noctua NH-L9a-AM4 Chromax è una scelta eccellente per chi cerca un dissipatore ultracompatto per CPU e APU AMD Ryzen come i popolari 3700X, 3600, 3400G o 3200G." (Matteo Carrara, PC-Gaming.it)
10.02.2020 // Bits and Chips

NH-L9a-AM4 chromax.black Review

Seppur aiutato dalle basse temperature in un ambiente di test aperto ed affidato ad CPU non troppo calorosa, devo ammettere che il piccolo Noctua NH L9a chromax.black in prova mi ha davvero sorpreso. Non credevo che un dissipatore dalle dimensioni a momenti insignificanti (Capaci di farlo quasi scomparire tra i componenti installati sulla mia AsRock B450 Steel Legend), accoppiato ad una ventola così piccola ma dalle grandi potenzialità, potesse rendere così bene!
Test verdict: "Inutile dire a questo punto che, nel caso in cui vi serva un dissipatore di queste "dimensioni e capacità", il Noctua NH L9a chromax.black vale tutti i soldi che costa, anche se la cifra è maggiore o uguale a quella di prodotti ben più grandi." (Vincenzo Mancuso, Bits and Chips)
10.02.2020 // mod-your-case.de

NH-L9a-AM4 chromax.black Review

Auch wenn der Kühler von der Kühlleistung her nicht mit großen Kühlern mithalten kann, konnte der Kühler unser Testsystem auch unter einer andauernden Belastung auf einer Temperatur halten, welche einen reibungslosen Betrieb des Systems zulässt. Im Vergleich zum Boxed-Kühler verrichtet der NH-L9a-AM4 chromax.black diese Aufgabe nicht nur etwas besser, sondern auch um einiges leiser. Für alle, die noch mehr aus dem Kühler herausholen wollen, liegen dem Lieferumfang zusätzliche Schrauben bei, mittels welchen man einen stärkeren 92 x 92 x 25 mm großen Lüfter montieren kann. Wie wir es in der Zwischenzeit von anderen Noctua Produkten kennen, wurde auch der neue NH-L9a-AM4 chromax.black sehr hochwertig verarbeitet.
Test verdict: "Mit dem NH-L9a-AM4 chromax.black hat Noctua seinen kompakten NH-L9a-AM4 in einer komplett schwarzen Version neu aufgelegt und spricht mit seinen kleinen aber feinen CPU-Kühler nun auch Nutzer an, welche auch in ihrem Mini-ITX-System großen Wert auf die Optik legen." (Patrick Seus, mod-your-case.de)
07.02.2020 // Glob3trotters.com

NH-L9a-AM4 chromax.black Review

Overall, given the testing circumstance employed, the L9a chromax.black is so far the best solution since it has such a great cooling performance to noise output ratio.
Test verdict: "Overall the L9a is still the best low profile air cooler when it comes to the perfect balance of cooling performance, noise output and build quality. It can even handle a modest overclock which is very welcomed, a testimony to its proficiency." (Alex Nistor, Glob3trotters.com)

NT-H2 3.5g

  • Further improved second generation of the award-winning NT-H1 with even better thermal performance
  • Not electrically conductive and non-corroding
  • Excellent long-term stability (usage time on the CPU up to 5 years)
  • 3.5g pack for around 3-20 applications (depending on CPU size, e.g. ~3 applications for TR4, ~20 for LGA1151)
NH-L9a-AM4 chromax.black

NT-H2 10g

  • Further improved second generation of the award-winning NT-H1 with even better thermal performance
  • Not electrically conductive and non-corroding
  • Excellent long-term stability (usage time on the CPU up to 5 years)
  • 10g pack for around 9-60 applications (depending on CPU size, e.g. ~9 applications for TR4, ~60 for LGA1151)
NH-L9a-AM4 chromax.black


  • Cleaning wipes for removing thermal compounds such as Noctua NT-H2 and NT-H1
  • Ideal for cleaning the contact surface of the heatsink as well as the heat-spreader of CPUs, GPUs or other chips
  • Pre-moistened with a custom detergent mixture for easy and efficient cleaning
  • Large size (15x12cm) is usually enough to clean both the chip and the cooler
  • Pack contains 20 individually packed wipes
NH-L9a-AM4 chromax.black

You can either buy from our local sales partners or directly from us via our official Amazon and eBay stores:

As an Amazon Associate, we earn from qualifying purchases.


Installation Manual (PDF)

Information Sheet (PDF)

The mounting brackets don’t touch the mainboard, is this an issue?

No. The mounting brackets are not meant to touch the mainboard and the flexibility of the brackets is required to create the appropriate contact pressure. There should be up to 3mm (Intel) or 4mm (AMD) space between the mainboard and the mounting brackets when the cooler is correctly installed.

nh-l9 mounting bar spacing

Can I upgrade my existing Noctua cooler to socket TR4 or SP3?

Unfortunately, it is not possible to upgrade existing Noctua heatsinks to support the AMD TR4 and SP3 sockets for Ryzen Threadripper (X399) and Epyc CPUs. TR4/SP3 CPUs have much bigger heatspreaders (as compared to e.g. LGA2066 or AM4 processors) and the contact surfaces of standard Noctua heatsinks would cover only about half of these heatspreaders, which would result in insufficient cooling performance. On top of that, the heatpipes of bigger cooler models like the NH-D15 or NH-D15S would completely block the RAM slots on many TR4/SP3 motherboards. For this reason, Noctua has introduced the new NH-U14S TR4-SP3, NH-U12S TR4-SP3 and NH-U9 TR4-SP3 cooler models that feature bigger contact surfaces and have been tailored to fit TR4 and SP3 systems. Please choose these models for AMD Ryzen Threadripper and Epyc systems.

How can I determine if the motherboard’s UEFI BIOS is overclocking my processor by default and deactivate this automatic overclocking?

Most motherboard vendors allow their overclocking-enabled products (e.g. those with Intels X- or Z-series chipsets) to run the processor at increased clock speeds by default, without requiring any user action at all. Since TDP (Thermal Design Power) limits are usually also disabled by default, this leads to the CPU exceeding the rated TDP to a varying degree, depending on the used applications and their workloads. Due to the increased heat output of the CPU, you may see higher CPU temperatures than expected.

In order to find out if your motherboard is overclocking your processor by default, please enter the UEFI BIOS and select the “advanced” or “overclocking” menu. There you should be able to find options such as “MultiCore Enhancement” (options: enabled/disabled), “CPU Ratio Apply Mode” (options: all/per core) or similar. To disable the automatic overclocking, adjust the settings either to “disabled” or “per core” and make sure that the individual multipliers match the original specifications.

In doubt, please contact your motherboard vendor for detailed instructions on how to disable this feature.

Which Noctua fan or CPU cooler should I buy? How to choose the right model?

Not sure which Noctua product to buy? Our detailed buying guides for fans and CPU coolers help you to choose the model that works best for you.

How much torque should be applied when tightening the screws of a Noctua CPU cooler?

All screws should be tightened gently until they stop without using excessive force. Please do not exceed the following values for maximum tightening torque:
Screw typeMax. torque
NM-SSC1 screws for fixing the fastening brackets to the base of the heatsink0.5 Nm
NM-ITS1 thumb screws for fixing Intel mounting bars0.5 Nm
NM-ALS1 screws for fixing AMD mounting bars0.6 Nm
Spring-loaded screws for fixing the heatsink to the mounting bars0.6 Nm

I have difficulties installing the cooler, can you help?

Please refer to the installation manual and our video installation guides for detailed instructions on how to install the cooler.

My case supports CPU coolers of up to XXXmm height, which model should I choose?

Please refer to our TDP guide in order to select the cooler that offers the best cooling performance at a given height.

Can I install a Noctua cooler in my system from Acer, Dell, HP or Lenovo?

Systems from Acer, Apple, Dell, HP, Lenovo or other major brands often use motherboards which differ slightly from the specifications issued by Intel and AMD. While those changes are usually subtle, they can lead to compatibility issues with coolers that were built to comply with these specifications.

Even in case the cooler is mechanically compatible and can be installed, other issues can occur, e.g. proprietary fan connectors, BIOS errors due to a low fan speed, shutdowns, etc. Some of these problems can be avoided with some technical knowledge, but especially BIOS related issues can often not be resolved.

Due to the large number of possible issues that cannot be resolved with different mounting parts alone, Noctua does not officially support systems from Acer, Apple, Dell, HP, Lenovo or other major brands.

What Thermal Design Power (TDP) is this cooler recommended for and how much Watt (W) of heat can it dissipate?

Please refer to our CPU compatibility list for information on maximum recommended TDP and heat dissipation.

How should I clean my Noctua cooler?

Dust: Fans and heatsinks inside computer cases tend to accumulate dust over longer periods of usage. In order to maintain maximum performance, please clean your fan and heatsink regularly. For cleaning, please first remove the fan from the heatsink and clean it using a duster, slightly moist tissue or canned air. Please be careful not to use too much force in order to prevent any damage to the fan. Please do not use a vacuum cleaner as this may apply excessive force to the fan and do not put the fan under running water as water residues inside the motor may lead to short circuits. Please also note that the fan is not designed to be taken apart by the user. Removing the impeller from the frame will break the sealing of the bearing and results in a loss of warranty. Before reinstalling the fan, clean the heatsink itself with a duster or vacuum cleaner. Do not use water to clean the cooler. Finally put the fan back on and connect it to your motherboard fan header or fan controller.
Thermal paste residues: Whenever you take off the heatsink from the CPU, we recommend to clean the CPU as well as the base of the cooler before re-applying thermal paste and re-installing the cooler. You can either just wipe the base and the CPU clean with a dry, lint-free tissue or, for more thorough cleaning, use a lint-free tissue moistened with either a mild solution of washing-up liquid or isopropyl alcohol. Do not put the cooler or CPU under running water. Note that both the base of the heatsink and the CPU should be dry, free from residues of thermal compound and free from grease before re-applying thermal paste and re-installing the cooler.

Does the coating of the chromax.black coolers affect performance?

Thanks to thoroughgoing optimisations of the coating material and process, the chromax.black models provide the same, renowned quiet cooling performance as their regular, non-coated counterparts.

Why is my Ryzen 3000 processor getting so hot? Why are Ryzen 3000 CPUs running hotter than previous generation Ryzen CPUs with the same TDP rating? Is there anything wrong with my cooler?

The latest Ryzen 3000 processors (except APU models) differ from previous Ryzen generations in that they are no longer based on a single, large chip but use a multi-chip approach with smaller chips instead. Depending on the exact model there can be one (6 and 8-core models) or two (12 and 16-core models) actual CPU-Dies (CCD) on the package. Each processor also uses an I/O-Die (IOD), which contains things like the memory controller, PCIe controller, connections to the motherboard chipset and other functions.

Because of this design change and the switch to a smaller 7nm manufacturing process, the heat distribution of the overall processor is much different from older 14nm and 12nm based single-chip Ryzen processors with a similar power draw.

Depending on the exact CPU model, its specified TDP value and possibly extended power limits (precision boost overdrive), a single CPU-die can create a heatload of up to 130W easily, whereas the I/O-die usually creates a heatload of about 10W. Due to the small size of the CPU-die, the heat density (W/mm²) of this chip is very high. For example, a 120W heatload at a chip-size of 74mm² results in a heat-density of 1.62W/mm², whereas the same heatload on an older Ryzen processor with a chip-size of 212mm² gives a heat-density of just 0.57W/mm².

This large difference in heat-density is the reason why newer Ryzen 3000 processors become much warmer at similar heatloads than their predecessors.

Furthermore, Ryzen 3000 CPUs are using the rated temperature headroom (up to 95°C) quite aggressively in order to reach higher boost clocks. As a result, it is absolutely no problem and not alarming if the processor runs into this temperature limit. The clock speed and supply voltage will be adjusted automatically by the processor itself in order to remain within AMD’s specifications and to prevent overheating.

Due to the higher heat density, higher thermal limits and more aggressive boost clock usage, it is perfectly normal that Ryzen 3000 CPUs are reaching higher temperatures than previous generation Ryzen CPUs with the same TDP rating. Higher CPU temperatures are normal for Ryzen 3000 processors and not a sign of that there is anything wrong with the CPU cooler.

Do you have a question concerning one of our products? Please use this form to pose a question!