Re: Opinions AMD64 vs EM64T vs Itanium II

> 
> Are there any technical reasons to prefer AMD64 (Opteron), EM64T
> (Xeon) or Itanium II CPUs? Are there things that don't work in RedHat
> on any of those platforms with either RHEL3 or RHEL4? 
> 
> Beyond that, we are currently running 32-bit on 32bit Xeon processors
> - I'm think I can also run 32-bit RedHat on either the AMD64 or EM64T
> chips - is that correct?

you can run a 32 bit OS on x86-64 (EM64T and AMD64) yes. If you really
care about 32 bit application compatibility I would have to say that
Itanium II isn't really for you; while if you want to run native number
crunching applications, Itanium might be an option. (People and
magazines tend to laugh a bit about Itanium; for certain applications,
especially number crunching it's a great CPU)

While there is 32 bit application compatibility on Itanium, it's not as
smooth and transparent as it is on x86-64; if you really depend on this
heavily I would consider a nice Xeon 5100 series box :)

The one limit you have with a 32 bit OS is the total amount of memory;
you don't really want to go over 32Gb, and even 16Gb can have issues...


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