I apologize for the late response, but I missed Professor Ripley's reply. For 
what it is worth, I have successfully compiled a 32-bit ATLAS-based BLAS for 
Windows for the Core-i7 that passes the make checks and library tools tests 
(which may be found at 
<http://lib.stat.cmu.edu/R/CRAN/bin/windows/contrib/ATLAS/C2i7/> for those 
interested in either testing or using it). Using this BLAS, I find a speedup of 
around 500% for matrix multiplications of 1000x1000 dense matrices. 
Unfortunately, in the environment in which I operate, I am currently 
constrained to a 32-bit operating system. If and when the transition is made to 
64bit, I will gladly use  Professor Nakama's versions, although none of them 
are optimized for Core i7 (Sandy Bridge or otherwise) CPUs. 

As the necessity to remove the xerbla remains, and implementing it does allow 
for the proper compilation of R under Windows, I will just have to archive that 
information myself and use it the next time I need to update the BLAS. I am 
thankful that the Windows-based MAKEFILE still allows for the compilation of 
Rblas.dll linking to an ATLAS-based BLAS, and although I regret that the 
manuals will no longer contain that information, I certainly defer to the 
expertise and experience of those much more knowledgeable than I in matters 
programming, compilation, and R.

Thank you,

Avraham Adler

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