Alpine 11 Pro fits Intel sockets 775 (used by Pentium 4, Core 2 Duo, Core 2 Quad, etc) and 1156 (recently launched, used on Core i3, Core i5 and some Core i7 models) CPUs. In both cases, first you need to unscrew the cooler from the plastic frame shown in Figure 7.

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Figure 7: Holding frame.

After that this frame must be installed on the motherboard using four pegs. In Figure 8, you can see how this frame looks like after being installed on the motherboard.

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Figure 8: Frame installed.

Finally, put the cooler in the frame and fasten both the screws that hold the cooler in place. In Figure 9, you can see how the cooler looks like after installed inside our chassis. Note that there almost no room left between the cooler and the chipset heatsink.

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Figure 9: Installed on case.