Anyone got an opinion on this? Need to know as I'm about to setup a server that uses an AMD Opteron processor.

It depends more on the compiler and compiler options than the distro.

You could recompile everything from source if you wanted to every single ounce of performance out of your processor.

You would want to run the x86_64/amd64 version of any Linux distribution you do run, but the specific distribution does not matter. They are almost all compiled with near-identical options and will run within a hair's breadth of any other on the same hardware.

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Do you have branded server (HP, DELL, IBM, etc.) or own-assembled one?
If it is HP or DELL - you may consider RedHat (Fedora), or CentOS (RedHat clone compatible with RHEL at binary level), or OpenSUSE.
You need x86-64 (AMD64) version.
Both HP and DELL sell and support RedHat and SuSE. But of course support from vendor would cost you extra money.
That's why Fedora, OpenSuSE or CentOS may be a very good option.

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Vadim Plessky

I'd prefer OpenSuse and would suggest the same to you. Many enterprises do use SLES 10 SP2.

OpenSUSE 11.1 is an excellent distribution. I run it on my laptop and it is the only distribution out of several I tried that allows it to suspend to RAM and successfully resume. The unit has an Intel GM45 IGP like almost all 14.1" business notebooks and the Intel graphics drivers are quite broken now, often breaking suspend and resume. The openSUSE devs must have found a workaround for at least that one issue...

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