The Noctua NH-D15S is a modified variant of the well-known NH-D15, that increases the overall compatibility of the cooler with small form factor systems, such as mini-ITX and micro-ATX. One of the main differences between the regular NH-D15 and the S variant featured in this review, is the usage of a single 140mm fan. The heatsink and heatpipes have an asymmetrical layout and a slight offset, this is done to gain more space for the PCIe slots of the motherboard.
The heatsink has a dual-tower design and uses 45 fins per tower. The main change from the NH-D15 model is the asymmetrical shape of the heatpipes and the position of the heatsink. The fins are made from untreated aluminum and thus, the sides of the heatsink are prone to fingerprints.
To increase the space available for the RAM slots and VRM heatsinks of the motherboard, the lower 7 fins of the heatsink are shorter. This is done on both towers of the cooler and in equal measure.
Just like the NH-D15, the S variant uses six nickel-plated copper heatpipes to transfer the heat away from the CPU surface. The heatpipes have an outer diameter of 6mm and are arranged in the traditional U-shape. The baseplate is soldered to the heatpipes while an additional plate is placed over the heatpipes to create a sturdy assembly.
The base of the cooler is made from a single nickel-plated copper piece; the surface is polished to an almost mirror like reflection. Circular grooves are present from the manufacturing process; however, they are shallow enough to not cause air bubbles when the thermal compound is applied.
The NH-D15S uses a single NF-A15 PWM 140mm fan, this model is found on many high-end Noctua CPU Coolers, thanks to its 120mm mounting spacing and numerous other improvements. This fan also uses the second generation of the SSO Noctua bearing system, with improved reliability and stability. The dimensions for the fan are: 140 x 150 x 25 mm.