Microsoft has released various optional updates / fixes. Check out the full list to see if they may apply to you.
Update for Windows Vista (KB945149)
Install this update to improve the graphics performance for multiple Graphics Processing Unit (GPU) scenarios on a system running Windows Vista.Update for Windows Vista for x64-based Systems (KB945149)
Install this update to improve the graphics performance for multiple Graphics Processing Unit (GPU) scenarios on a system running Windows Vista.Update for Windows Vista for x64-based Systems (KB945435)
Install this update to resolve an issue where delays are experienced while accessing a WebDAV share for the first time on a system running Windows Vista.Update for Windows Vista for x64-based Systems (KB945145)
Install this update to resolve an issue where a user is prompted for Windows Live Passport credentials every time a document is accessed on a WebDAV site from a new workspace.Update for Windows Vista (KB945435)
Install this update to resolve an issue where delays are experienced while accessing a WebDAV share for the first time on a system running Windows Vista.Update for Windows Vista for x64-based Systems (KB938660)
Install this update to resolve a performance issue on Windows Presentation Foundation (WPF)-based programs on a system running Windows Vista.Update for Windows Vista (KB938660)
Install this update to resolve a performance issue on Windows Presentation Foundation (WPF)-based programs on a system running Windows Vista.Update for Windows Vista for x64-based Systems (KB944652)
Install this update to resolve an issue in administrative MMC snap-ins where icons display incorrectly on a Windows Vista-based computer with Windows Server 2003 Administration Tools Pack installed.Update for Windows Vista (KB944652)
Install this update to resolve an issue in administrative MMC snap-ins where icons display incorrectly on a Windows Vista-based computer with Windows Server 2003 Administration Tools Pack installed.Update for Windows Vista (KB945145)
Install this update to resolve an issue where a user is prompted for Windows Live Passport credentials every time a document is accessed on a WebDAV site from a new workspace.