NVIDIA has purposefully de-optimized its PhysX realtime physics engine when it is run on the CPU, according to research carried out by Real World Tech.
The article goes on to claim that NVIDIA makes use of the x87 instruction set for floating-point math rather than the more modern, and vastly superior, SSE.
The truth is that there is no technical reason for PhysX to be using x87 code. PhysX uses x87 because Ageia and now Nvidia want it that way.
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