Brent L. Bates wrote:

>      This discussion has got me wondering though and a bit confused.  What
> platforms can run `X86_64' and which only the `32bit' one?  I guess one could
> run the 32 bit OS on 64 bit hardware.  
Yes, an Opteron (or EMT64)  system will happily run a 32-bit OS
(in fact, I'm booting an Opteron server off a 32 bit Knoppix CD today, 
but that is another story.)
More relevantly, I have installed a cluster of Opterons which were 
initially run with 32 bit SuSE and later reinstalled with 64 bit, 
without problems.

What are the advantages of the 64 bit
> over the 32 bit, if any, and visa versa?  Thanks for any clarification.
That would be an ecumenical question.
AFAIK (and very much sticking my neck out here!) 64 bit platforms allow 
use of much larger physical memory.
Add to that the SSE registers and Hypertransport bus of the Opteron 
platform allowing higher bandwidth access to memory.
I expect some more robust answers to this one as the Intel horse is 
coming up the home straight.

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