Clock speed

The clock speed of a processor is the number of times per second the clock ticks. It’s measured in hertz (Hz), which represents one tick per second.

For example, a clock speed of 4.8 GHz (gigahertz) means that the clock ticks 4.8 billion times per second.

How does clock speed affect performance?

The higher the clock speed, theoretically, the more fetch-execute cycles the processor can carry out per second, which means it can execute more instructions per second, and therefore perform better.

In reality, there are lots of things that can be the bottleneck. It’s all well and good having a high clock speed, but if our RAM is slow, for example, then it’s going to have to wait for ages for the data to arrive back from RAM before we can work on it.