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Installing DirectX 8.1b (for End-Users)

Document Summary: Instructions on installing DirectX 8.1b for end-users (people installing games, applications, etc.). Only required if you're using Windows 98 or ME, Windows 2000, or Windows XP without Service Pack 1.

Document Changelog: Created.


DirectX is a Windows technology that enables higher performance in graphics and sound when you're playing games or watching video on your PC. For more information, visit Microsoft's DirectX Technology Overview page at:


DirectX 8.1b

DirectX 8.1b is the minimum DirectX version required for using UnrealEngine2, and contains bug fixes in the DirectX Runtime that are required for the engine to run on cards without hardware transform and lighting. e.g. TNT2, Kyro I/II, Voodoo 3, Radeon 7000, etc.

Earlier versions of DirectX, including DirectX 8.0, 8.0a and 8.1 do not have these fixes. A minimum of 8.1b is required.

Windows 98/Me


Windows 2000


Windows XP

Windows XP users should upgrade to at least Service Pack 1a to update their version of DirectX to 8.1b:


DirectX 9.0b

DirectX 9.0b is the latest DirectX version available, and also includes these fixes. You do not need to upgrade to 9.0b if other software on your machine does not require it. You can download DirectX 9.0b from the main DirectX web site below: