Aussie legend Cameron McBride and good friend Tony Sanchez from Citrix sent a heads up to me recently on some performance related hotfixes. They are specific to proc and SP1. Nevertheless they are definitely worth applying for the best performance.
Issue 1: Performance is not as awesome as it could be on Westmere or Sandybridge chipsets
In this scenario, the performance of the computer may decrease.For example, the following performance issues may be encountered: