Chambers <ben### [at] pacificwebguycom> wrote:
> If what you want to do is compare different 64 bit systems to each 
> other, then it's possible that this will suit your needs completely. 
> Especially considering that the major bottleneck in POV is the double 
> precision FPU, which is the same either in 32 or 64 bit mode.

  Except that the de-facto chip for floating point calculations in 64-bit
intel-based processors is SSE, while in 32-bit systems it's the FPU. This
means that most compilers will usually automatically use SSE when compiling
for an x86-64 target and FPU when compiling for an x86-32 target.

  (x86-64 processors have a FPU and modern x86-32 processors have SSE, but
in the former the FPU is "deprecated" and thus compilers will by default
generate SSE code because x86-64 is guaranteed to have support. In the latter,
however, SSE support is not necessarily guaranteed and thus compilers will
by default generate FPU code, unless specifically told to generate SSE code.)

  There may be relevant differences in speed between a 32-bit FPU-using
executable and a 64-bit SSE-using executable when run on a 64-bit system
because of this.

-- 
                                                          - Warp

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