Clock speed - GCSE Computer Science Definition
Reviewed by: James Woodhouse
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What is clock speed?
In GCSE Computer Science, clock speed refers to how many Fetch-Decode-Execute cycles the CPU can perform per second. It is measured in Hertz (Hz), with modern CPUs operating in Gigahertz (GHz), meaning billions of cycles per second.
How does clock speed affect CPU performance?
A higher clock speed means the CPU can fetch and execute instructions faster. For example, a 3.5 GHz processor can handle 3.5 billion cycles per second, improving the overall speed of a computer system.
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