Noctua NM-AMB15 chromax.black Offset AMD AM5 Mounting Bars, 78mm Pitch

The NM-AMB15 are offset AM5 mounting bars for Noctua CPU coolers with 78mm mounting pitch that require their mounting points at the east and west side of the socket for optimal orientation.

By offsetting the heatsink 7mm towards the south side of the CPU socket, more pressure is applied above the CPU’s CCD(s). This improved contact, exactly at the processor’s hotspot can help reduce CPU temperatures in the range of 1-3°C. Replacing the standard mounting bars and re-using the original spacers and screws, the NM-AMB15 is a simple yet highly efficient solution to help optimise thermal performance on AM5-based AMD Ryzen CPUs.

Offsetting for the hotspot

AMD’s latest Ryzen processors have their Core Complex Die(s) not at the centre, but slightly towards the south side of the CPU. By shifting the heatsink right above the hotspot created by the CCD(s) and applying optimal contact pressure where it matters the most, thermal performance can often be improved significantly.

Cooler, faster, quieter

While the results can vary due to different heat flux densities, tolerances of both the CPU and heatsink as well as other factors such as thermal paste application, the offset mounting can yield significant improvements with typical reductions in core temperatures ranging between 1 and 3°C on high-end AM5 processors. These gains can be used to let the CPU run cooler, to achieve higher boost clock frequencies or to reduce fan speeds and noise levels.

One bar, two positions

The offset mounting bars feature two hole sets, one for offsetting the cooler 7mm towards the south side of the socket and one for the standard, non-offset position. The latter can be used in the unlikely case that the offset position causes compatibility issues, such as clearance problems with motherboard heatsinks or PCIe cards.

Compatible with AM5 and AM4

While primarily designed for AM5, the offset mounting bars can also be used on AM4, where they may yield slight improvements on Ryzen 5000 and 3000 series processors. However, the improvements when using the offset mounting position on these CPUs tend to be much smaller, typically <1°C instead of the 1-3°C gains that can be achieved on AM5.