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RE: AMD vs Intel

From: Bonate, Peter <Peter.Bonate>
Date: Mon, 18 Nov 2019 17:15:47 +0000

Leonid - when you say different. What do you mean? Fixed effect and random effects? Different OFV?

We did a poster at AAPS a decade or so ago comparing results across different platforms using the same data and model. We got different results on the standard errors (which related to matrix inversion and how those are done using software-hardware configurations). And with overparameterized models we got different error messages - some platforms converged with no problem while some did not converge and gave R matrix singularity.

Did your problems go beyond this?


Peter Bonate, PhD
Executive Director
Pharmacokinetics, Modeling, and Simulation
1 Astellas Way, N3.158
Northbrook, IL 60062
(224) 205-5855

Details are irrelevant in terms of decision making - Joe Biden.

-----Original Message-----
From: owner-nmusers <> On Behalf Of Leonid Gibiansky
Sent: Monday, November 18, 2019 11:05 AM
To: nmusers <nmusers
Subject: [NMusers] AMD vs Intel

Dear All,

I am testing the new Epyc processors from AMD (comparing with Intel Xeon), and getting different results. Just wondering whether anybody faced the problem of differences between AMD and Intel processors and knows how to solve it. I am using Intel compiler but ready to switch to gfortran or anything else if this would help to get identical results.
There were reports of Intel slowing the AMD execution in the past, but in my tests, speed is comparable but the results differ.


Received on Mon Nov 18 2019 - 12:15:47 EST

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