There have been reported several incidents of AMD FX processors not working properly with the new 4.0 Firewire driver. We have learned that there are several Win7 bugs and subsequent hotfixes related to FX processors. The AMD FX processors use a unique dual-core module architecture codenamed “Bulldozer”, which current versions of Windows® 7 were not specifically architected to utilize. In essence, Windows 7 sees only one half available cores and randomly assigns threads to them.
Applying these hot fixes resolved problems where the 4.0 Firewire driver failed to run on AMD FX motherboards.
It is required that you install KB2645594 first and then KB2646060
KB2645594 - An update is available for computers that have an AMD FX, AMD Opteron 4200, AMD Opteron 6200, or AMD Bulldozer series processor installed and that are running Windows 7 (http://support.microsoft.com/kb/2645594)
Currently, the CPU scheduling techniques that are used by Windows 7 and Windows Server 2008 R2 are not optimized for the AMD Bulldozer module architecture. This architecture is found on AMD FX series, AMD Opteron 4200 Series, and AMD Opteron 6200 Series processors. Therefore, multithreaded workloads may not be optimally distributed on computers that have one of these processors installed in a lightly-threaded environment. This may result in decreased system performance for some applications.
Currently, the CPU Power Policies that are used by Windows 7 and Windows Server 2008 R2 are not optimized for the dual core AMD Bulldozer module architecture. This architecture is found on AMD FX series, AMD Opteron 4200 Series, and AMD Opteron 6200 Series processors. This can result in decreased system performance with multithreaded workloads in lightly-threaded environments.