11.2 Troubleshooting the Hardware Box
11.2.5 CPUs
Symptoms of a processor error can include slow performance, POST beep errors, or a system that is not operating properly. These errors usually indicate that an internal error has occurred. Internal errors might also cause failures to be intermittent. The CPU might begin a task, then fail. If the system continuously counts RAM or freezes while counting the RAM, the CPU is creating the errors and might need to be replaced.

Requirements for a CPU to work with a motherboard include voltage, socket type, and clock speeds.

Cooling Issues
Most CPUs will have an onboard fan. This provides cooling directly to the CPU. If the system freezes after being on for a while, then the CPU fan might be malfunctioning. The CPU is overheating and freezes due to improper cooling of the CPU. Proper maintenance of internal components will help prevent the costly repair to the CPU. Keep the computer in a well-ventilated area, clean vents, ensure case slots are replaced, and dust the inside of the computer. The proper cooling fan for the specific CPU is also required.

CPUs can also become loose due to the expansion of metals when heated and their contraction when cooling. Metal fluctuation will eventually cause the CPU to loosen. Visually inspect the CPU, and if it appears slightly loose, push it back into place.

Voltage Supply Issues
CPUs must be set to receive the correct voltages to run properly. Motherboards that use Socket 5, Socket 7, or Super Socket 7 chips need to use voltage regulators. Those that use Socket 370, slot 1, slot A, or socket A use an automatic voltage regulation feature. Figure shows the different types of CPU designs. This capability allows the CPU to determine the voltage setting automatically. Typically, the voltage regulators are built into the board. They must be set at the proper voltage, or the CPU can be damaged.

Properly inspect and examine the motherboard, CPU chip, and motherboard documentation to find the correct CPU voltage.