Contrary to some misconceptions, these SIMD capabilities did not amount to the processor being “128-bit”, as neither the memory addresses nor the integers themselves were 128-bit, only the shared SIMD/integer registers. For comparison, 128-bit wide registers and SIMD instructions had been present in the 32-bit x86 architecture since 1999, with the introduction of SSE. However the internal data paths were 128bit wide, and its processors were capable of operating on 4x32bit quantities in parallel in single registers.

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