Microsoft has released an update for Windows 7 to optimize the performance of AMD Bulldozer CPUs

This article introduces an update that optimizes the performance of AMD Bulldozer CPUs that are used by Windows 7-based or Windows Server 2008 R2-based computers. Currently, the performance of AMD Bulldozer CPUs is slower than expected. This behavior occurs because the threading logic in Windows 7 and in Windows Server 2008 R2 is not optimized to use the Simultaneous Multithreading (SMT) scheduling feature. This feature was introduced in the Bulldozer family of AMD CPUs.

Note This issue may occur when you use applications that run in multiple threads.

After you install this hotfix, Windows 7 and Windows Server 2008 R2 fully support AMD Bulldozer CPUs. Therefore, the CPUs operate at the expected performance level.

  An update to optimize the performance of AMD Bulldozer CPUs