Socket 478 is used by the older Pentium 4 and Celeron socket 478 models. The process of applying thermal grease to those processors is similar to the process of socket 754 and 939 processors.

First make sure the processor surface is completely clean and free from dirt and remains of thermal grease form past applications, see Figure 28.

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Figure 28: Checking if the processor surface is clean.

Using a small spatula (which can be made out by cutting a piece of the hard transparent plastic from the processor box), apply some thermal grease on the center of the processor. Don’t worry about covering the whole processor area because the cooler pressure will make it uniform. See Figures 29 and 30.

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Figure 29: Applying the thermal grease.

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Figure 30: Thermal grease correctly applied.

The next step is to install the cooler over the processor, of course.