How to apply thermal paste

Thermal paste optimises the contact between the CPU and the cooler, whether it be an AIO, air cooler, or a custom loop, because the surfaces of the CPU and the blocks are never perfect. There are micro-irregularities.

Each of these micro-irregularities reduces the heat exchange performance between the two, that's where the thermal compound comes in, it fills them in to optimise the contact between the two.

There are several application approaches that have evolved over time. The most modern approach is to use applicators and stencils to optimise the amount and thickness of paste applied.

Our XTM70 kit includes a spreader and two triangular stencils to optimise the amount and distribution of paste.

We can see that the distribution is complete and that there is very little overflow outside the CPU or too thick of a layer after the coldplate of the cooler has been installed.

A similar approach with the XTM60, which does not come with a stencil, is to manually spread a thin layer with the included credit card sized applicator card.

The result is a very good distribution but a slightly greater thickness than we found with the previously mentioned stencil approach.

Now one of the oldest and probably still the most widely used, with a pea-sized dot in the centre.

We can see that the distribution of the paste is circular, so it's slightly overflowed on the long edges of the CPU, and left the corners devoid of paste. The corners are not as hot as the central area, so this is passable, but sub-optimal.

We can see that the edges and corners of the CPU contain little or no paste. Again, a passable approach, but it could be better.

The distribution is not perfect, but it results in more comprehensive coverage than the vertical lines or the dot method. Thermal paste is not conductive so the overflow is nothing to be concerned about, but it's a bit messy. The X shape is more artistically fulfilling than the vertical lines, which is nice, but less satisfying than the pretty stencil pattern.

At the end of the day, all these methods are sufficient, but the stencil does result in the most even coverage. Regardless of how you choose to apply the thermal paste, just remember that too much is preferable to too little. It might create a slight mess, but will not result in any issues from a functionality standpoint.