Bit size — the amount of data that can be operated on at any given time. Intel's Pentium processor supports 32-bit operations, whereas the Itanium supports 64-bit operations. Operations performed on the data are relatively simple and include addition, subtraction, or retrieving data from memory.
Processor clock speed — a measure of the rate at which the CPU performs its operations. Modern high-end computers tout clock speeds of 1 GHz to 2 GHz.
Theoretically, the raw performance of a 1GHz 32-bit processor is double that of a 500MHz 32-bit processor. However, architectural factors, such as the type of cache memory and the bandwidth of the connections between the CPU and the memory, significantly affect a system's overall performance.
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