Asus Motherboard AP130-E1 - Manual (Page 28)

2-8 Chapter 2: Hardware information
2.3.3 Installing the heatsink and fan
The Intel ® Pentium ® 4 Processor requires a specially designed heatsink
and fan assembly to ensure optimum thermal condition and performance.
The retention module base is already installed on the motherboard
upon purchase.
You do not have to remove the retention module base when installing
the CPU or installing other motherboard components.
Follow these steps to install the CPU heatsink and fan.
1. Place the heatsink on top of the installed CPU, making sure that the
heatsink fits properly on the retention module base.
When you buy a boxed Intel Pentium 4 Processor, the package
includes the heatsink, fan, and retention mechanism.
In case you buy a CPU separately, make sure that you use only Intel
certified heatsink and fan.
Your boxed Intel Pentium 4 Processor package should come with
installation instructions for the CPU, heatsink, and the retention
mechanism. If the instructions in this section do not match the CPU
documentation, follow the latter.
Retention Module Base
CPU Heatsink