Hello.
I would like to present an article about tweaking Barcelona via WPCREDIT. There are the main actions you should do to tweak almost any setting\timing in the Barclona and A64 in generaly integrated memory controller. And not only memory. The article is based on BIOS and Kernel Developer's Guide (BKDG) For AMD Family 10h Processors. There is a link to it in the article.