Heatsink Lapping for Better Thermal Efficiency and Reduce TempsThis guide shows you how to perform heatsink lapping which involves polishing a CPU/GPU heatsink to make better thermal contact.
To maximize the efficiency of your CPU cooler, it's vital to ensure as much of its surface is in contact with the CPU heat spreader as possible. This guide is here to help you get the most out of your heat sink.
What is Heatsink Lapping?
Thermal compounds help improve the thermal efficiency of a heat sink rough surface by 'filling' in the cracks with a highly heat conductive material, but to have even better cooling, the extreme modder ensures that both surfaces are as flat as possible. The process of flattening out a cooler is called heatsink lapping.
Why Lap a Heat Sink?
- Heatsink lapping or sanding can greatly decrease heat when overclocking.
- Heatsink lapping is relatively safe, and if you have the correct sandpaper, it's free..
- I said it's free, and it reduces heat from the CPU. Do I need to say more?
Firstly, in a picture, you can see in the reflection that the surface is curved (not flat) and on closeup, you can see little ridges where it has been machined. These ridges and troughs prevent good contact with the CPU surface. In the second picture, you can see the 'splatter' pattern, where the thermal compound makes good contact and where it makes poor contact.
This is not a how-to article; there are loads of good tutorials on this online, so we don't need another one. This is just my experience of it.
Embarking on this journey, I spent about 10 minutes sanding with 300 grit sandpaper, followed by another 10 with 600 grit. I then progressed to 1200 grit and finally, I used metal polish. After this meticulous process, I ensured to clean the surface with isopropanol, removing all traces of the polish, which can act as a heat insulator.
Heatsink Lapping Results
Notice the reflection and how clear and undistorted it is. That is because the surface is like a mirror now. So shiny I can take pictures of the house opposite on the surface!
As a testament to the effectiveness of this method, my temperatures (as recorded by MBM5) saw a significant drop. From 49C idle to 48C and 65C load to 60C, the improvements were undeniable. This outcome, achieved through my own efforts, was truly rewarding.
