Wasn't it Warp who wrote:
>Mike Williams <nos### [at] econymdemoncouk> wrote:
>> The figures there are for the POV 3.5 benchmark and go as low as 
>> 11 mins 7 for a single CPU and 1 minute 12 for 128 CPUs in parallel.
>
>  How reliable those results are? What measures, if any, do the maintainers
>of the site take to verify that the results are genuine?
>
>  For example, I find it difficult to believe that a 1GHz Itanium2 is
>almost twice faster than a 3GHz P4, a 2.8GHz Xeon or a 2.5GHz Athlon XP
>(specially considering that it's the *only* entry using an itanium, so
>we don't have comparable times with other itanium systems).
>  If the result is genuine, I would certainly like to know how it is
>possible.

Most of the math used in POV is floating point. An Itanium 2 clains to
run at 1.2 cycles per floating point operation. Various models of
Pentium 4 claim to run at between 6.0 and 6.9 cycles per flop. Various
models of Pentium 3 Xeon claim to run at between 3.3 and 4.7 cycles per
flop. An Athlon XP claims to run at 4.3 cycles per flop.

So, theoretically,
1GHz Itanium 2   should perform a GigaFLOP in 1.3 seconds
3GHz Pentium 4   should perform a GigaFLOP in 2.0 to 2.3 seconds
2.8GHz Xeon      should perform a GigaFLOP in 1.2 to 1.7 seconds
2.5GHz Athlon XP should perform a GigaFLOP in 1.7 seconds

>  There are many other entries which are difficult to believe as well.
>For example a 1.8GHz Opteron being faster than a 2.5GHz Athlon XP.

1.8GHz Opteron @ 3.6 cycles per flop = GigaFLOP in 2.0 seconds

All other things being equal, one might expect the Athlon to be a little
faster than the Operon (assuming we can trust the claimed cycles per
flop figures). However, other things are never quite equal. For example
the fact that the Opteron is listed as running Linux and the Athlon as
running Windows XP will have made some difference. Things like cache
sizes and memory speeds may also have an effect.

-- 
Mike Williams
Gentleman of Leisure

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