The device used to remove the processors heat is the cooler. Each processor requires a specific type of cooler. The use of an inefficient or wrongly dimensioned cooler can cause overheating problems.
But the cooler alone doesn’t solve the overheating problem. There’s another “bad guy” in the story: heat transfer between the processor and the cooler.
From the microscopical point of view, the physical contact between the processor and the cooler isn’t perfect. Imperfections that exist both on processor surface and cooler surface prevent the 100% perfect contact between them.
As both surfaces aren’t perfectly even, minuscule gaps of air are formed when putting them together. As air is a terrible heat conductor (its conductibility coefficient is 0.026 W/m°K), the heat will pass with more difficulty from the processor to the cooler, which can result in overheating.
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Figure 1: Air gaps formed by the junction of processor and cooler.
To solve the problem and improve the heat transfer between the processor and the cooler, we should apply thermal grease between them in order to fill in the tiny gaps of air. By doing so, the heat transfer between the processor and the cooler is more easily made, since the thermal grease has higher conductibility coefficient than the air.
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Figure 2: Gaps of air filled by thermal grease.
Thermal grease can be found in electronics parts stores and its use is indispensable. Besides, it’s a really cheap component.
On the next pages we will talk about how to correctly apply the thermal grease and also about the most common mistakes made when applying thermal grease.
