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- 32-bit vs. 64-bit systems 19 answers
I have pondered that some say "32-bit is old news" because you are limited in RAM without cutting around, such as with PAE. Assuming first that the following factors weigh in on the processor's speed itself:
Microarchiterual design, meaning things like cache size, implementation of microcode (if applicable), data/address bus and register connections, and, of course, design principles or structures.
Bus speeds, such as FSB speeds (front-side bus) and the related such.
Special features, like parallelism, "hyper threading", "compute units", off-loading work with a co-processor or background processor, multi-core environments, etc.
Assuming (and we know all of those things weigh in on speed factors) the processor is 32-bit, would the fact that it is alone 64-bit make it faster just because of increased bit-width, memory addressing, size, etc.?
Basically, with two identical processors, would the 64-bit one be faster generally in machine code decoding, fetching, accessing memory, MMIO, computations, etc., than the prior 32-bit clone?