Microsoft XNA Game Studio Express is a revolutionary new toolset and technology which makes creating great video games for Windows-based PC?s and the Xbox 360 console (with an active XNA Creators Club subscription) easier than ever.
System Requirements and Prerequisites
Only supported on Microsoft® Windows® XP SP2 (all editions) at this time. Windows Vista will be available only in a future beta release of XNA Game Studio Express. Hardware requirements are identical to those for Visual Studio 2005 plus a graphics card that supports DirectX 9.0c and Shader Model 1.1 (Shader Model 2.0 support recommended). This release requires Microsoft Visual C# 2005 Express Edition to be installed before proceeding. You can install Visual C# Express from the Visual C# Express Download Page. However, other members of the Visual Studio 2005 line of products, for example Visual Studio 2005 Professional, can co-exist with XNA Game Studio Express on the same computer.
Microsoft XNA Game Studio Express 1.0
XNA Game Studio Express Readme
XNA Team Blog
System Requirements and Prerequisites
Only supported on Microsoft® Windows® XP SP2 (all editions) at this time. Windows Vista will be available only in a future beta release of XNA Game Studio Express. Hardware requirements are identical to those for Visual Studio 2005 plus a graphics card that supports DirectX 9.0c and Shader Model 1.1 (Shader Model 2.0 support recommended). This release requires Microsoft Visual C# 2005 Express Edition to be installed before proceeding. You can install Visual C# Express from the Visual C# Express Download Page. However, other members of the Visual Studio 2005 line of products, for example Visual Studio 2005 Professional, can co-exist with XNA Game Studio Express on the same computer.
Microsoft XNA Game Studio Express 1.0
XNA Game Studio Express Readme
XNA Team Blog