Forget about Windows Vista's DirectX 10, Microsoft is delivering a preview of DirectX 10.1 associated with the first service pack for the operating system. The Direct3D 10.1 Tech Preview is an integer part of the August 2007, DirectX Software Development Kit, and is designed to provide the evolution of the current Direct3D 10.0. Version 10 of DirectX, available exclusively via Windows Vista, includes Direct3D. In this context, Microsoft revealed that the Direct3D 10.1 Tech Preview is connected with Vista SP1, but the company failed to provide a timetable for the availability of the service pack.

"The Microsoft Direct3D device driver interface (DDI) is a graphics interface that allows vendors to provide hardware acceleration for Direct3D. The interface is flexible, allowing vendors to provide Direct3D acceleration according to hardware capabilities. Driver writers implement the Direct3D DDI as an integral part of the display driver," Microsoft described.

"Direct3D 10.1 is an incremental, side-by-side update to Direct3D 10.0 that provides a series of new rendering features that will be available in an upcoming generation of graphics hardware. TextureCube Arrays which are dynamically indexable in shader code. An updated shader model (shader model 4.1). The ability to select the MSAA sample pattern for a resource from a palette of patterns, and retrieve the corresponding sample positions. The ability to render to block-compressed textures. More flexibility with respect to copying of resources. Support for blending on all unorm and snorm formats," reads Microsoft's description of the Direct3D 10.1 Tech Preview.

The Redmond company has repeatedly denied speculations that it will backport DirectX 10 to Windows XP, and additional rumors of third-parties delivering Vista's graphics technology to older versions of Windows, or in the context of DirectX 9 and lower hardware. While Windows Vista is closing in on its six months of availability on the market, Microsoft estimates that in excess of 10 million gamers have upgraded to Windows Vista just to reek in the benefits of DirectX 10. The latest statistics from Redmond reveal that Vista sold over 60 million licenses from January 30.

Still, the Direct3D 10.1 Tech Preview will only come in handy after the re-release of Vista SP1. Currently, Microsoft admitted that a private beta of the service pack is under way, and that a public beta will follow at an unspecified date later this year. "This tech preview provides an early look at these features and the handful of new APIs that support them. The August 2007 Direct3D 10.1 Tech Preview requires the Windows Vista SP1 Beta which will be available to MSDN subscribers once it is publicly released," Microsoft added.