If you feel that Windows Vista is buggy, Microsoft knows this too. Hence the release of Windows Vista Performance Update (KB 938979) which intends to improve the the performance of Windows Vista system in certain scenarios. KB938979 hotfixes is not released via Windows Update or Automatic Updates yet, and may include as part of upcoming Windows Vista Service Pack 1 (SP1), but you can download the update package from Microsoft Download Center.

KB938979 attempts to fix the following performance issues and bugs to increase performance, responsiveness and reliability of Windows Vista :

  • You experience a long delay when you try to exit the Photos screen saver.
  • A memory leak occurs when you use the Windows Energy screen saver.
  • If User Account Control is disabled on the computer, you cannot install a network printer successfully. This problem occurs if the network printer is hosted by a Windows XP-based or a Windows Server 2003-based computer.
  • When you write data to an AVI file by using the AVIStreamWrite function, the file header of the AVI file is corrupted.
  • When you copy or move a large file, the “estimated time remaining” takes a long time to be calculated and displayed.
  • After you resume the computer from hibernation, it takes a long time to display the logon screen.
  • When you synchronize an offline file to a server, the offline file is corrupted.
  • If you edit an image file that uses the RAW image format, data loss occurs in the image file. This problem occurs if the RAW image is from any of the Canon EOS 1D and Canon EOS 1DS digital SLR camera models.
  • After you resume the computer from hibernation, the computer loses its default gateway address.
  • Poor memory management performance occurs.

Download Windows Vista Performance Update for x86-based System here.
Download Windows Vista Performance Update for x64-based System here.

Failed WGA validation check? Check out direct links to setup file.

KB938979 update can be applied to Windows Vista Enterprise, Business, Home Premium and Ultimate edition. Windows Genuine Advantage validation required so your Windows Vista must be genuine and legitimate.

The download is in Microsoft Update Standalone Installer .msu format. But it works just like a normal .exe executable, simply double click to install the update.

Microsoft also releases another KB938194 update to improves reliability of Windows Vista.

The KB938979 disables support for BCDEDIT /SET LOADOPTIONS DDISABLE_INTEGRITY_CHECKS commands that disable driver signing permanently to allow unsigned drivers to install on 64-bit Vista. So if you’re using patches such as Windows Vista TCP/IP tcpip.sys maximum half-open connections patch or various hacks such as TimerStop.sys and TimerStop64.sys (also applied by TimerLock auto patcher), make sure you remove the patches or cracks first.