In this episode, NEDC (the Network for Engineering and Device Cooling) conducts a detailed examination of two different types of thermal pads, focusing on how their thermal conductivity affects their performance in real-world applications. While the comparison focuses on conventional silicone-bound gap pads, the same principle applies across material families, silicone-free gap pads, high-conductivity pads like the GAP PAD TGP 18000SF 18 W/m-K, and graphite TIMs like HPMS flexible graphite all show that the W/m-K number on the datasheet is only one of several variables that determine real-world thermal performance.
The primary distinction between these two pads lies in their thermal conductivity—one has a lower thermal conductivity than the other. Typically, thermal conductivity is a key metric for evaluating the effectiveness of a thermal interface material (TIM), as it indicates the material’s ability to transfer heat from a hot surface (such as a CPU or GPU) to a cooler heat sink or other cooling solution.
At first glance, one might assume that the pad with the higher thermal conductivity would outperform the lower-conductivity pad, as it should theoretically transfer heat more efficiently. However, the episode delves into the complexities of heat transfer and performance in thermal management systems, showing that the situation isn’t always that straightforward.