Before you buy a CPU, make sure that it is compatible with the existing motherboard. Manufacturers’ websites are a good resource to investigate the compatibility between CPUs and other devices. When upgrading the CPU, make sure the correct voltage is maintained. A Voltage Regulator Module (VRM) is integrated into the motherboard. You can configure the CPU voltage setting with jumpers, switches located on the motherboard, or settings in the BIOS.

Multicore processors have two or more processors on the same integrated circuit. Integrating the processors on the same chip creates a very fast connection between them. Multicore processors execute instructions more quickly than single-core processors and have increased data throughput. Instructions can be distributed to all the processors at the same time. RAM is shared between the processors because the cores reside on the same chip. A multicore processor is recommended for applications such as video editing, gaming, and photo manipulation.

High-power consumption creates more heat in the computer case. Multicore processors conserve power and produce less heat than multiple single-core processors, thus increasing performance and efficiency.

The speed of a modern processor is measured in GHz. A maximum speed rating refers to the maximum speed at which a processor can function without errors. Two primary factors can limit the speed of a processor:

The front-side bus (FSB) is the path between the CPU and the Northbridge. It is used to connect various components, such as the chipset and expansion cards, and RAM. Data can travel in both directions across the FSB. The frequency of the bus is measured in MHz. The frequency at which a CPU operates is determined by applying a clock multiplier to the FSB speed. For example, a processor running at 3200 MHz might be using a 400 MHz FSB. 3200 MHz divided by 400 MHz is 8, so the CPU is eight times faster than the FSB.

Processors are further classified as 32-bit and 64-bit. The primary difference is the number of instructions that can be handled by the processor at one time. A 64-bit processor processes more instructions per clock cycle than a 32-bit processor. A 64-bit processor can also support more memory. To utilize the 64-bit processor capabilities, ensure that the operating system and applications installed support a 64-bit processor.

One of the most expensive and sensitive components in the computer case is the CPU. The CPU can become very hot. Many CPUs require a heat sink, combined with a fan for cooling. A heat sink is a piece of copper or aluminum that sits between the processor and the CPU fan. The heat sink absorbs the heat from the processor and then the fan disperses the heat. When choosing a heat sink or fan, there are several factors to consider.

The CPU is not the only component in a computer case that can be adversely affected by heat. A computer has many internal components that generate heat while the computer is running. Case fans should be installed to move cooler air into the computer case while moving heat out of the case. When choosing case fans, there are several factors to consider:

NOTE: The direction of air flow created by all the fans in the case must work together to bring the cooler air in while moving the hotter air out. Installing a fan backwards or using fans with the incorrect size or speed for the case can cause the air flows to work against each other.