If you’re building a new PC, shopping for a prefabricated one, or just want to learn more about computers, the processor is the perfect place to start. A processor (CPU) is literally the brain of a computer, determining how quickly it can run programs, execute commands, process data, and, well, “think.” Much like the human brain, a CPU defines a computer’s personality. The efficacy of every other component ultimately relies on how competent a processor is.
A processor’s speed, responsiveness, and multitasking abilities are measured by its number of cores and clock speed. Put simply, more cores enable a processor to interact with more applications at once, and faster clock speed determines how quickly those interactions are carried out. Brands like Intel and AMD offer consumer-grade CPUs with up to eight cores and clock speeds exceeding 5.0 gigahertz, but in reality most users need far less than that.
Key considerations
Cores
Within a CPU, there are several smaller independent processors called cores. Modern examples have between 2 and 32 of these cores (consumer products often cap out at 16); each core can handle its own tasks. If a CPU has more cores, it’s more adept at multitasking and juggling various applications at once.
Clock speed
Cores determine how many programs a computer can handle simultaneously, but the clock speed determines how quickly each task is executed by the processor. Clock speed is measured in gigahertz (GHz), and it specifically measures the frequency of electrical pulses coming from the motherboard to the processor. Along with the number of cores a processor has, clock speed is extremely important for high-end gaming performance.
Contemporary CPUs can adjust their clock speeds up and down based on the particular task as well as temperature. These speeds are often listed as “minimum” clock speeds and “maximum,” “boost,” or “turbo” speeds.
Threads
If a CPU is a computer’s brain, and each core is its own lobe, then the processor threads essentially act like nerves, controlling individual command lines. Each computer application likely utilizes multiple threads, which is why some new processors boast multithreading capabilities to expand multitasking performance. In layman’s terms, more threads equals better performance during high-intensity tasks like video editing, rendering, and animation.
TDP
Computer processors use a significant amount of energy, and thus they create a significant amount of heat. A CPU’s heat output is measured by its thermal design profile (TDP), and this refers to the maximum amount of heat in watts a chip puts out at stock speed. This is vital to know because you need a CPU cooler able to dissipate that amount heat or you risk damaging your system and reducing performance.
Cache
Each processor has an onboard cache of temporary memory to facilitate quick communication between the CPU and random access memory (RAM). Three levels of cache work together inside a processor. The speediest is L1, but it has the least memory storage. L2 is larger and slower by contrast, and L3 is even larger and slower. L3 feeds instructions to the L2 cache, which sends instructions to L1 to fully complete a task. The more memory you have across all three levels (measured in gigabytes), the faster your CPU will be.
Features
Overclocking
The term “overclocked CPU” is often used in computing discussions, but it’s commonly confused with “boost” and “turbo” CPU speeds. They’re very different, though.
Boost and turbo: These speeds exist within a processor’s stock clock speed range and are opened up depending on computer temperature and current energy use.
Overclocked: An overclocked CPU involves modification of the motherboard to force the processor to operate faster than it did out of the factory. This can unlock significant performance potential if done correctly, but it can also place additional stress on other components and generate more heat. Before you consider overclocking, research your components thoroughly and consider additional cooling to prevent issues.
Intel vs. AMD
The Intel vs. AMD CPU debate has raged for years, and while it’s sure to continue moving forward, both brands produce exceptional products at a variety of price points.
Historically, AMD has been the low-cost, high-value option. AMD is still the best “bang for your buck” choice in some respects, but the company has achieved near performance parity with Intel with its Threadripper series, modern architectures, and pricier options. For instance, the AMD Ryzen 9 3950X boasts 16 cores, 32 threads, and a 3.5 GHz base clock with a 4.7 GHz boost. Intel’s i9-9900K has 8 cores, 16 threads, and a 3.6 GHz base clock with a 5.0 GHz boost.
At the end of the day, both brands have excellent offerings for a variety of tasks. Rather than strictly adhering to one brand, we recommend you judge each CPU on its specifications, performance, and price, and make your final decision on a case-by-case basis.
“Depending on your setup, you may want to consider a dual-chambered design for your PC tower. This allows you to isolate your power supply from your CPU, GPU, RAM, and other components, improving aesthetics as well as heat management for maximum performance. “