SMT technology is not supported by any operating system and is one of the reasons Bulldozer has been getting pants reviews. Microsoft described the hotfix as the means to bring the 8-core chips to the level of performance they were supposed to show.
While this would have been all cool, it surprised the hell out of AMD and it seems that within 24 hours Microsoft pulled the patch completely. AMD said that "There are actually two updates needed for AMD Bulldozer CPU architecture and Microsoft just posted just the first patch one. Sadly the first one was not a lot of good without the second and AMD did not believe users would benefit in any way from it.
A spokesman said that the patch was originally scheduled for the first quarter 2012 and then the users will see tangible performance benefits when using Windows 7 and Windows Server 2008 R2 operating systems. Those who downloaded part one might want to consider uninstalling it and forgetting they ever saw it.