What Is Clock Speed?


  • CPU speed is determined by how many calculations the processor can perform per cycle.

  • Clock speed is expressed in gigahertz — billions of cycles per second. Higher clock speeds generate more heat.

  • Intel Turbo Boost technology enables processors to safely and efficiently increase clock speed beyond their usual operating limits.

  • Overclocking1 a CPU enables significant performance gains but requires more power and generates more heat.



The performance of your CPU — the “brain” of your PC — has a major impact on the speed at which programs load and how smoothly they run. However, there are a few different ways to measure processor performance. Clock speed (also “clock rate” or “frequency”) is one of the most significant.2

If you’re wondering how to check your clock speed, click the Start menu (or click the Windows key) and type “System Information.” Your CPU’s model name and clock speed will be listed under “Processor.”

What Is Clock Speed?

In general, a higher clock speed means a faster CPU. However, many other factors can come into play, as well.

Your CPU processes many instructions from different programs every second. Some of these instructions involve simple arithmetic, while others are more complicated. The clock speed measures the number of cycles your CPU executes per second, measured in GHz (gigahertz).

In this case, a “cycle” is the basic unit that measures a CPU’s speed. During each cycle, billions of transistors within the processor open and close. This is how the CPU executes the calculations contained in the instructions it receives.

Frequency is more operations within a given amount of time, as represented below.

A CPU with a clock speed of 3.2 GHz executes 3.2 billion cycles per second. (Older CPUs had speeds measured in megahertz, or millions of cycles per second.)

Sometimes, multiple instructions are completed in a single clock cycle; in other cases, one instruction might be handled over multiple clock cycles. Since different CPU designs handle instructions differently, it’s best to compare clock speeds within the same CPU brand and generation.

For example, a CPU with a higher clock speed from five years ago might be outperformed by a new CPU with a lower clock speed, as the newer architecture deals with instructions more efficiently.

Recent features like the Intel® Thread Director allow the latest gen Intel processors to intelligently distribute workloads to multiple cores. That’s one reason why newer processors often outperform older ones on benchmark tests even when they have similar clock speeds.

Within the same generation of CPUs, a processor with a higher clock speed will generally outperform a processor with a lower clock speed across many applications. This is why it’s important to compare processors from the same brand and generation. The K-series of Intel® Core™ processors, for example, denotes a set of chips that are unlocked and allow for overclocking, indicating that they can achieve more ambitious clock speeds than their peers in the same generation.

For more information on how to interpret Intel® Core™ processors by their naming conventions, read our guide.

How Does Clock Speed Affect Gaming?

Before the advent of multi-core CPUs, clock speed was viewed as the key spec for comparing single-core processors. Today, it’s taken into consideration alongside many other factors, like:

  • The number of cores the CPU contains
  • The size and efficiency of the CPU cache
  • The amount of power the CPU consumes

The impact of clock speed on an individual game depends on the game’s engine and the tools used to create it. For example, FromSoftware’s Elden Ring uses a proprietary game engine that leans heavily on single core performance3. On the other hand, Infinity Ward’s Call of Duty: Modern Warfare 2 is designed to take full advantage of core multi-threading. This allows the game to hit impressive performance benchmarks even when using older, slower processors — provided it has enough cores to work with.3

These examples show that specific benchmarks are the best way to assess CPU performance in a particular game engine. However, clock speed remains a good general guide to the relative performance of processors within a product family.

What Does Turbo Frequency Mean?

Intel processor specifications list both Max Turbo Frequency and Processor Base Frequency. The processor base frequency refers to the its regular operating point, while the Max Turbo Frequency refers to the maximum speed the processor can achieve using Intel® Turbo Boost Technology.

Intel Turbo Boost Technology enhances clock speed dynamically to deal with heavy workloads. It works without requiring any installation or configuration by the user. The technology judges the amount of heat the system can tolerate, as well as the number of cores in use, and then boosts clock speed to the maximum safe level.

Base Processor Frequency and Max Turbo Frequency are two core performance metrics that refer to different usage scenarios. For high-intensity gaming, the turbo frequency is the more important metric.. Given adequate cooling, this is the speed your CPU will operate at when dealing with heavy gaming workloads such as traveling through a highly detailed environment, or calculating AI behavior on an enemy turn in a strategy game in the most CPU-intensive titles.

How Do You Adjust Your CPU Clock Speed?

The term “overclocking” refers to speeding up the CPU clock for more processing power. As mentioned above, Intel CPUs with a “K” in the name have an unlocked “multiplier” for easy overclocking when paired with a motherboard chipset that supports overclocking.

Overclocking can yield improved FPS, even for high-end CPUs like the latest gen Intel® Core™ processors. Intel® Speed Optimizer provides one-click overclocking for all Intel® processors. This means experts and beginners alike can optimize overclocking performance safely.

The CPU multiplier (sometimes called the “CPU ratio”) expresses the CPU’s performance as a multiplier of the CPU Base Clock (or BCLK) speed. A CPU multiplier of 46 and a base clock of 100 MHz, for example, results in a clock speed of 4.6GHz. Note that the BCLK in the system’s BIOS settings is not the same as the “Processor Base Frequency” referred to in Intel specs — the latter refers to the overall CPU clock speed when Intel Turbo Boost Technology isn’t activated.

The BCLK sets not only the speed of the CPU, but also the speed of memory, PCIe bus, CPU cache, and more. It’s easier for overclockers to simply adjust the CPU multiplier than to change the BCLK, which can cause instability by affecting many components at once.

Why Does Clock Speed Matter?

CPU clock speed is a good indicator of overall processor performance. Though applications like video editing and streaming are known to rely on multi-core performance, many new video games still benchmark best on CPUs with the highest clock speed.

Clock speed is a useful metric for comparing processor models in the same generation. When selecting a processor for a new gaming computer, it provides at-a-glance information about the general performance of products in the same lineup, like the latest gen Intel® Core™ Processor family. For more specialized use cases, individual benchmarks are usually more appropriate.