Thanks for responding.   For my interests and motivations for running these
tests, see my "Results..." posting below.

>>   I still think that this benchmark has not very much relevance anymore
with
>> current computers. If one computer renders the skyvase in 5 seconds and
>> other in 6 seconds, that doesn't tell anything about which one is faster.


This has become conventional wisdom, useful if not applied too broadly.   To
universalize it, however,  is to err as those who apply narrow and specific
tests to a GENERAL computing machine.

To test for IMAGE RENDERING, what is better than loading a CPU(s) completely
with the software it will be running?

Given that, we are left only with choosing a test protocol which will
approximate our kind of script programs-- and, yes, this does require
judgment.   Will we use fonts?  Fog?  Focal blur?  Textures?  How much of
each?

Note that my emphasis is directed from 'how fast is my machine?' to 'how
much WORK can I expect out of this machine?'    They are corollaries, to be
sure, but my interest lies more in workload scalability-- or moving to 'real
time' designing.   So far, I've found the results of my tests to be quite
relevant and informative.

[And, yes, for brief tests to be meaningful, one must minimize variables
like disk accesses (another program's), etc.   A lovely example:  in both
Win98 and NT, as quickly installed and (un)configured on my '1 GHz' test
machine, one of the four or six or eight instances of POV might run TWICE as
fast.
    Turns out to be the instance which has the focus.  Had to click on
desktop after starting all.
    Beyond that, discarding extremes, my results were very consistant.  A
percent or two.]

> With regard to other elements
>effecting render times I agree that a more robust scene should be developed
>to really test the power of modern processors and ultimately their true
>raytracing speed rating. I leave that task to those more competent than
>myself to decide what that may be but I'm sure there must be some routines
>in Pov that could be used for a reliable benchmark. Probably a combination
>of math functions, high order primitives, and complex surface finishes that
>require large numbers of ray intersection tests.

When we shift the focus from the work a particular machine will do to
TESTING CPUs and machines in general, Ken, it seems to me than NM's
criticism becomes more applicable.   For example, if an x86 compiler used on
POV source is inferior to an Alpha compiler, the Alpha might look 50% faster
for certain POV programs.  Clearly, we are not just testing hardware.

Matt

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