Kenneth wrote:
> I've been curious about this topic as well.  So do I understand that SSE2
> is a machine architecture/chip thing? Or is it somehow also an operating
> system thing? I've tried reading up on the subject, but I still don't
> understand it fully.

SSE2 is a set of SIMD extensions to the instruction set of the CPU. SIMD =
Single Instruction, Multiple Data. Basically, instead of doing:
a[0] = b[0] + c[0]
a[1] = b[1] + c[1]
a[2] = b[2] + c[2]
a[3] = b[3] + c[3]

the CPU can be told to add b[0]-b[3] with c[0]-c[3] and store it in
a[0]-a[3], and it will do all four additions *at the same time*, since the
hardware has multiple adders.

That's of course oversimplified. And may be even wrong if *I* understood it
wrong :)

> I'm currently running the non-SSE2 version of POV-Ray 
> (v3.6.1c) on 32-bit Windows XP SP3, on a 64-bit single-core AMD Athlon
> machine. Can I use the SSE2 version of POV? And will it give me better
> performance (if only slightly?) Sorry to be such a dummy about this. :-S

SSE2 will give you better performance. May be very small difference, but it
will be something for sure.

"SSE2 was first introduced by Intel with the initial version of the Pentium
4 in 2001. AMD added support for SSE2 with the introduction of their
Opteron and Athlon 64 ranges of AMD64 64-bit CPUs in 2003."

So your CPU does support it. I heard *all* 64-bit CPUs support SSE2 (and you
don't need a 64-bit OS to use SSE2).

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