Subject: Re: CCL:Opteron or Nocona ?

From: Christian Boehme <Christian.Boehme * gwdg.de>
Date: Tue, 10 May 2005 11:41:46 +0200

Dear Luigi,

Luigi Cavallo schrieb:
> we are going to invest some money for a few computers, and we have to
> make a decision between the AMD-Opterons and the Intel-Nocona. What's
> better ? We are experienced with the Opterons, but we have no idea about
> the Noconas...
> 
> Major codes to run on them will be classical QM packages as ADF, G03, TM,
> some AIMD as CPMD, and possibly some classical MD as gromacs.

We recently purchased a 32 dual-processor Opteron (2GHz) cluster. We 
used CPMD and several artificial benchmarks on Opteron and Xeon (3GHz) 
machines to come to this decision. With CPMD we found that the advantage 
of the Opteron over the Xeon was very significant for 32-bit memory 
intensive applications running on both processors of a dual processor 
box (Intel compiler on both architectures). When using just one 
processor, the Xeon scored much better. As Intel has not changed the 
memory interface of the Nocona, I do not think this trend would be 
different for 64-bit applications. Regarding Fortran compilers, from our 
experience both the Intel and the Portland can now be used to make 
production quality 64-bit binaries for the Opterons. Best wishes

Christian

-- 
Dr. Christian Boehme
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