> A scene file I have takes 45 minutes
> running on a single core. This same scene file takes 20 minutes under
> Windows XP (standard binary distribution) on a Pentium M 1.86GHz laptop.

	Your observation is indeed quite surprising, especially given that
this Opteron processor should be faster than the Pentium-M.  Without your
scene at hand, at the moment I have no idea why it performs less than twice
slower compared to the other binary / OS / machine specs.

	However here are some thoughts:

- try running the official benchmark with your binary, and compare the result
with those on the page linked by Florian.  I suppose you should get a CPU time
in the order of 1200-1250 seconds (64-bit binary, single core).  Otherwise,
it's likely that something is wrong with your binary, maybe a problem with
the 64-bit environment.  You might also run the benchmark using the official
32-bit Linux binary just to figure out if your system is running stable.
Running the benchmark with the Pentium-M on Windows might also be helpful
to get an idea of what is the expected speed ratio between the two machines.

- in case your k8 machine passes the test(s) above, try running your scene
with the official 32-bit Linux binary.  In principle you should run even
more slower.  Otherwise, there might be something very specific in your scene
(some POV feature that is not used in the official benchmark) that reveals
an optimization problem in your binary (e.g. with SSE2 usage) or instability
in the system (e.g. again a possible 64-bit specific problem, a buggy math
or C library).

- try running with 3.7.0.beta.16.linux-x86-64.  This binary was prepared using
the same compiler as yours and similar optimization flags.  Due to the many
changes in 3.7, the binary might render your scene faster on a single core.
Of course, in such a case you might consider running on as many cores as are
available on this machine  :-)


	- NC

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