Tom Melly wrote:

> "Kari Kivisalo" <kar### [at] kivisalonet> wrote in message
> news:3A717C79.10257149@kivisalo.net...
> > Tom Melly wrote:
> > >
> > > Question: If 3DNow speeds up float calcs, why is it only of benefit to
> > > graphics and not all apps. using floating point calcs.?
> >
> > WinAmp uses 3DNow to decode mp3s.
> >
>
> Yes - I gathered that it applied to multi-media (hate that term) - this is
> partly what confused me. MM as a generic set of apps is hardly likely to
> benefit from something unless that something can also benefit non-MM apps.
> The answer would appear to be the 3dnow only works on single-point.

My understanding of 3dnow, and intel's counterpart Katimi new instructions, is
that it merely allows you to do the same instruction on several pieces of data
simultaneously.  Basically it saves clock cycles by not having to repeat the
same instruction.  Example multiplying normally you would input something like
this into the processor: data, data, multiply, data, data, multiply, data,
data, multiply... But with (single instruction multiple data) it would use a
single command to to input all the multiply's.  Well this is my understanding
of it.  I have never read the actual list of commands an intel processor
recognizes.

Dan Johnson

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