Bulldozer / Zambezi Microsoft Windows 7 hotfix patch(MS Pulled, More Testing)

An update to optimize the performance of AMD Bulldozer CPUs that are used by Windows 7-based or Windows Server 2008 R2-based computers is available

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.


this should also help the the new “Interlagos” Server Processors as well…

Sadly test results show that it made very little difference, in many of the tests it shows even worse results then before. At least there were a quite significant boost with Futuremark PCMark 7 and Crysis 2, but it’s not enough to save Bulldozer.

Source: http://www.sweclockers.com/artikel/14855-testresultat-amd-fx-8150-med-kb2592546-uppdaterad-schemalaggare-i-windows-7 (in Swedish)

The patch only resolves one issue for Bulldozer. This patch should help less threaded application to run a bit faster as the core turbo frequency can be enabled if threads are scheduled to run on less physical core. It won’t speed up the more threaded application though. Maybe a full implementation to truly take advantage of Bulldozer will only be available in Windows 8 after all.


Microsoft pulled the patch, We will probably have to wait for Windows 8 to see all of the improvements…
im sure they will re-release the patch for Windows 7 But, i doubt that it will ever be as fast as Windows 8


We have not yet tested Bulldozer with the hotfix, but don’t expect miracles as Microsoft is suggesting a 2-7% increase. Better scheduling for the Bulldozer CPUs will improve performance a bit, but not enough to close the gap in many scenarios. Windows 8 already has the new thread scheduler, and according to AMD’s own and third party tests the performance increase is up to around 10%,