1.2 - Types of Processor

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RISC and CISC
GPUs
Multicore & parallel systems

An instruction set is the complete list of machine code instructions a CPU is designed to execute as part of the FDE cycle.

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• CISC (Complex Instruction Set Computer) CPUs have a large set of complex instructions, so tasks can be achieved in fewer lines of code, but some instructions take multiple clock cycles.

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• RISC (Reduced Instruction Set Computer) CPUs use a smaller set of simple instructions, each designed to execute in a single clock cycle, making execution faster but sometimes requiring more instructions overall.

A GPU (Graphics Processing Unit) is a co-processor with thousands of smaller cores designed for parallel processing. This is in contrast to the CPU, which has fewer but more powerful cores.

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GPUs are used for rendering images, animations and video for fast, realistic graphics in games and multimedia. Because of their ability to handle many calculations at once, GPUs are widely used for non-graphical purposes too, such as machine learning, scientific simulations, data analysis and cryptocurrency mining.

A multicore processor has multiple independent cores on a single CPU chip. Each core can carry out its own FDE cycle, so tasks can be split up, enabling multitasking and faster processing. However, only software designed to use multiple cores will benefit from this increased performance.

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A parallel system uses multiple processors (or cores) working together on the same problem at the same time. This may involve multiple cores within one CPU or multiple CPUs in a single machine. Parallel processing greatly improves performance for tasks that can be divided into smaller sub-tasks, such as simulations and graphics rendering. However, some problems cannot be parallelised because they must be executed sequentially.