On Wed, Sep 26, 2007 at 09:03:10AM -0700, [EMAIL PROTECTED] wrote: > > andrew holway wrote: > > Multi reference quantum chem. Gaussian and Molcas.
Hi Andrew, You still need to tell us more about the jobs. I run large active space with large basis set CASPT2 jobs in MOLCAS. Since it's coded rather inefficiently, and the matrixes are huge, it doesn't not fit in memory and scratch files take up to 500Gb. So, you really need a 64bit machine with the fastest disk system you can get. It will be disk/IO bound and the processor will matter little. Also MOLCAS is a serial code in any Multi-ref part, so no use for extra cores/processors. Gaussian is rather limited for Multi-ref QM. So, I guess you will either use it for other kinds of calculations or will gave up using it in favor of only MOLCAS (or MOLPRO, GAMESS, etc...). > As usual, real use case tests are the most realistic predictor of > performance. Joe is right here, but sometimes the hardware is just not avalaible to testing. Regards, G -- Guilherme Menegon Arantes, PhD São Paulo, Brasil ______________________________________________________ _______________________________________________ Beowulf mailing list, [email protected] To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
