After the CPU support has been confirmed, or the BIOS flashed, it is time to unhook the external cables and open the PC case. You will only need access to the motherboard for this install, so save some time and leave the second side panel attached.

The next task is to create a working area that will be adequate to the task ahead. Installing a CPU is not a terribly demanding procedure, so a worktable or floor area should suffice. Keep in mind that you will be handling the processor with your bare hands and any stray static electricity may do it serious harm. Wearing a grounding strap solves this problem, but using a metal fixture or piece of furniture to discharge electricity can serve the same purpose.

There are basically two different CPU form factors, Slot and Socket, and each has a slightly different procedure for installation and removal.

First, detach the CPU fan header cable(s) from the motherboard or external ATX power cable, then disengage the Slot bracket from the CPU. There are several different methods of locking a Slot processor into place and you should refer to the motherboard documentation for exact instructions on unlocking the retention mechanism. Then, just remove the Slot processor by pulling it upwards firmly. It should come out easily and if there is resistance, confirm that all retention mechanisms have been disengaged. Place the CPU into an anti-static bag or other container and remove it from the work area.

For Socket 370/A processors, you also need to detach any fan header cables before starting on the CPU. Unlike a Slot CPU, the Socket variety has a separate heatsink/fan unit that must be taken out before the CPU. There are two clips holding the heatsink to the base of the socket, which must first be detached. This is done by exerting downward pressure on the primary clip (usually larger or features a swivel head) until it disengages. How difficult this will be depends totally on the heatsink design, and extremely troublesome heatsinks may need to be carefully helped off using a small implement or tool as a lever.

After the heatsink has been removed, raise the socket's retention arm into the “open” position and remove the CPU from the socket. The CPU should slide out easily, and if any resistance is encountered, then confirm that the retention arm is fully disengaged and that there are no other obstructions. Sometimes a pin on the back of the CPU can become slightly bent, meaning that just a bit more upward pressure is required to remove it.