A. Each new version of Windows normally brings enhancements to many areas, including DirectX. Windows Vista brought DirectX 10, which isn't available for Windows XP, and Windows 7 brings DirectX 11. The good news is that Microsoft released an update for Windows Vista SP2 to enable DirectX 11 on Oct. 27. The Platform Update for Windows Vista, KB971644, will upgrade your Vista computer to DirectX 11—you might have already installed it without knowing. You can run dxdiag.exe to check what version of DirectX you have.
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