Noctua 9 Series CPU Cooler Review

NH-D9L Features and Cooler Design

Features

Courtesy of Noctua

• Low-profile tower design for better airflow efficiency
• 3U compatibility
• 100% RAM compatibility
• 100% compatibility with PCIe cards on mini-ITX
• NF-A9 premium fan
• PWM support and Low-Noise Adaptor
• Dual fan ready
• SecuFirm2™ mounting system
• Compatibility with past and future sockets
• NT-H1 thermal compound
• 6 years warranty

The Noctua NH-D9L CPU cooler is a high performance, dual tower cooler, designed for maximum compatibility with any standard or small form factor-based system. The cooler features a single 92mm fan, nickel-plated copper heat-pipes and CPU base plate, and a densely-finned aluminum radiator. Noctua constructed the unit's four integrated heat-pipes out of copper to optimize heat absorption from the CPU base plate and heat transfer to the aluminum radiators. The aluminum radiators were designed to facilitate optimal transfer of the heat from the heat-pipes to the air medium. The thin nickel plating encasing the base plate and heat-pipes give them corrosion and scratch resistance, while not inhibiting heat transfer between the cooler's components.

Courtesy of Noctua

The NH-D9L's twin radiator towers were designed with a fin density of 13 fpi (fins per inch) with each tower being about almost 1.5x the thickness of a standard fan. Even though the unit uses smaller 92mm fans, the thickness of the radiators work to the NH-D9L's advantage. The radiator design gives the cooler its ability to work well with the smaller fans while adding surface area to better disperse heat from the aluminum fins as it is flows from the heat pipes. The heat-pipes are individually soldered to each of the aluminum radiator layers, ensuring an optimal heat transfer interface between the two dissimilar surfaces.

From the side view, you can better see the design optimizations implemented to enhance the units performance. Along the middle of both sides of each radiator is a fold-down spacer to give the fins rigidity, as well as to act as an air guide, created an air channel through which the center mounted fan can pull and push the air through. While the NH-D9L comes standard with only a single 92mm fan mounted in the unit's center, the radiator can support up to three fans simultaneously which gives the unit quite a performance boost with a negligible increase in operational sound. The side view of the unit best illustrates the true massiveness of the cooler. The integrated heat pipes are designed in a U-shape configuration, terminating in each of the towers with center of each heat pipe passing through the copper base plate. The unit's base has a top mounted, integrated hold down plate containing two spring-loaded screw-in nuts, giving the unit more than enough force for a solid mount with the CPU surface.

Each radiator's rectangular layered construction gives it the ability to maximize its internal surface area while minimizing its depth footprint for motherboard fit compatibility when used in its default or alternative, multi-fan configuration. The top plate is stamped with the Noctua name and acts at the termination point for the four embedded heat pipes. The heat pipes are soldered in place and capped to ensure heat pipe integrity, keeping the contents under pressure and promoting the phase change required for the heat pipe transfer medium to be effective. Integrated into the sides of the radiator are the standard dual hook configurations found on most Noctua coolers, used to hold the fans in place. The wire fan holds have two set of straight sections that lock into the hooked sections of the radiator to firmly secure fans to the front and/or rear sides of the radiator.

The unit's base plate is a seamless copper plate with nickel-plating to prevent corrosion and surface scratches. The base plate is fixed to an upper plate to which the hold down assembly is fixed, sandwiching the copper heat pipes. The heat pipes run through the center portion of the base plate to ensure optimal heat transfer. The base plate is machined flat and polished to a mirror-like sheen, ensuring a near perfect mating surface with the CPU.

There are absolutely no fit issues with the NH-D9L mounted to the test bench's Z87-based board. All DIMM slots remain easily accessible and the radiator towers are well above the surface level of the surrounding board heat sinks. You may have issues when using a front-mounted fan with the unit, but then it just becomes a matter of mounting the fan higher up the radiator to clear the memory modules.

From the closeup board shots, it becomes even more apparent how well Noctua designed the NH-D9L for board compatibility. In its default configuration, you should have no mounting issues with this cooler on any Intel-based board.

Things change a bit for the NH-D9L when attempting to use it in a tri-fan configuration, however. On the test LGA-115X board, the DIMM socket placement and height inhibited the use of a front mounted fan, forcing the loss of over 1/3 of the fan's cooling capacity when mounted. As a result, no test results were gathered for the cooler in tri-fan configuration on the Z87 board. In dual fan configuration, you are forced to mount the secondary fan to the rear of the unit as a result.

The test X99 board mounting is a totally different story. Because of the DIMM placement to the front and rear of the socket, the X99 board easily accommodated the NH-D9L cooler with three fans mounted to the unit.