What is clock speed? The key CPU and GPU spec explained

When diving deep into buying a new laptop, PC or component, you’ll have come across the all-important clock speed spec. If you’re not sure what it is, and why it’s important, we’re here to help.

Picking the best components for your custom PC or determining if the specs of your PC of choice are capable of what you need is not a simple task. One of the key metrics to consider is clock speed, but it’s just part of a broader picture.

Clock speed is relatively straightforward to understand on its own, even if it’s surrounded by complexity, so here are the key details on just what it means.

What is clock speed?

Clock speed represents how many instructions your CPU or GPU can process each second. In general, the more instructions, or cycles, your component can process and perform per second then the faster it will be.

It’s typically measured in GHz (gigahertz), previously MHz (megahertz) before speeds picked up. A clock speed of 6GHz would mean that 6 billion cycles are occurring per second.

Is a higher clock speed better?

The picture isn’t as clear as that though, with modern processors (CPUs) and graphics chips (GPUs) able to outperform older models with higher clock speeds due to the advancement of chip architecture. As such, it can be a key metric when comparing modern components with each other but you should always consider other factors such as the product generation and the architecture it uses.

What makes the difference is that, as technology moves forward, instructions can be handled differently within each cycle – such as multiple instructions being handled within a single clock cycle.

This also makes reviews and real-world performance testing of these products pivotal too, as it isn’t as black and white as higher GHz always means higher performance.

Clock speed is used as a metric across CPU and GPU components, meaning it serves an important purpose across all of computing. For those looking into PC gaming, you’ll find certain games favour high single-core GHz to get the best performance while some may favour multi-core capabilities. This is true outside of gaming too, with creative to coding workloads requiring different component priorities. Along with GHz, power consumption, number of cores and other factors greatly impact performance.

Outside of CPU and GPU components, and alongside their clock speeds, the specifications of your device’s RAM and SSD storage will play a key part in the performance as well.