Noctua NH-D15 G2 HBC Heatsink Review

For many computer builders the choice of CPU cooler often comes down to several factors.  Cost is usually the most critical while the type and overall performance are a close second.  When CPU overclocking was relevant there was a third factor which favored efficiency between thermal control and noise and would often make or break your overclocking success.  In this category there were few coolers who could best the Noctua NH-D15 and older Noctua NH-D14.

In this review we will be looking at the Noctua NH-D15 G2 HBC cooler.  This is a next gen version of the popular NH-D15 featuring the brand-new fan, larger 8 heatpipe configuration and designed specifically for the LGA 1700 processor.

For the longest time heatsinks were mostly a universal part meaning that, if the mounting hardware was included you could install the cooler on just about any processor and expect it to work.  While this process has carried on for years there were always issues with inconsistent performance.  Most of these problems were user error and to address this you would find some heatsinks with a convex shape which would promote good thermal paste spread and ensure that the center part of the cooler was properly contacting the center of the CPU.

The gamble is that not every CPU was guaranteed to have a flat heatspreader.  AMD processors were generally flat and to get the best performance you could “lap” or sand the base of the heatsink to match.  This would flatten the convex shape and provide better thermal transfer.  Many users did the same with Intel CPUs to get the desired result.

Noctua has addressed this in a very unique way by creating versions of their heatsink to best match the processor you plan to use. 

HBC or High Base Convexity, the version featured in this review, is optimized for the LGA1700 line of processors to better match the unique shape of the CPU heatspreader

LBC or Low Base Convexity is a variant of this cooler designed for relatively flat CPUs such as AMD AM5, AM5 and older Intel CPUs such as the LGA2066 and LGA2011.  This cooler could also be used on CPUs that have been lapped or have custom flat heatspreaders.

As mentioned before the NH-D15 G2 HBC comes with dual NF-A14x25r G2 PWM fans.  I got to see these fans up close during Computex 2024 and while the shape is rather unique the intention of the design is to provide a more efficient airflow that results in a vertical column of air and lower overall noise.

Noctua had a similar fan design that used their focus flow frame design with variable pitch stator guide vanes.  The purpose of this design was to redirect the air existing the fan from the typical cone shape into more of a column that not only helped to direct airflow but improved heatsink efficiency by providing more airflow over critical cooling components.

The new NF-A14x25r G2 PWM fan do the same using their unique blade shape forcing air to exit near the middle of the fan blade instead of flowing smoothly off the tip of the blade near the frame edge.  As with every high performance Noctua fan there is additional technology built in.  At the fan hub you will find textured fins that help to break up the stagnant air near the center of the fan.  You will also find guide vanes near the tips of each fan blade and the unique texture in the frame.  All of these things combined help to control overall turbulent noise, efficiency and airflow.