Shader Model 6.9 Released with Agility SDK 1.619 and DXC Updates
Microsoft has officially moved Shader Model 6.9 out of preview status, launching it alongside Agility SDK 1.619 and DXC version 1.9.2602.16. This release consolidates several features that have been in testing since 2025, providing developers with new tools for vector operations, ray tracing efficiency, and resource management. Additionally, a new preview runtime, Agility SDK 1.719-preview, has been introduced to test upcoming synchronization and video processing capabilities.
Shader Model 6.9 introduces significant changes to how HLSL handles data types and operations. The new feature adds support for Long Vector which enables elementwise processing of vectors that contain 4 to 1024 elements. This modification lets developers manage extensive data operations which they process through shaders.
The update makes all previously optional features required for standard 6.9 compliance.
- Native 16 bit Shader Ops: The feature has become a mandatory requirement that hardware must support.
- Int64 and Wave Ops: These requirements ensure that all compatible GPUs operate according to a common baseline starting from this point onwards.
- 16 bit Float Specials: The feature now supports IsNan() and IsInf() and IsFinite() functions for 16 bit floats together with the new IsNormal() function.
The SDK introduces DXR 1.2 which activates two crucial platform features into their complete production state.
- Shader Execution Reordering (SER): This tool lets users plan ray pathways to enhance their execution performance. The feature operates on Intel Arc B Series and NVIDIA RTX 4xxx+ GPUs but AMD RX 9000 series only offers API compatibility without active reordering capabilities.
- Opacity Micromaps (OMM): The technology enables better efficiency for alpha tested geometry through decreasing the requirement for expensive AnyHit shader calls. The feature runs on all current NVIDIA RTX 4xxx series and newer systems through hardware acceleration.
Microsoft has updated various core API functions to improve resource management based on developer feedback.
- Revised Resource View Creation: The new system allows users to measure buffer dimensions through byte offsets and sizes instead of element counts. The update introduces HRESULT returns which enable programs to handle errors more effectively through systematic error management.
- The new query heap type permits direct CPU timeline data resolution which reduces GPU overhead by enabling resolution of data through CPU processing.
- The hardware capabilities of specific systems permit users to establish dispatch limits which extend beyond the standard 65535 values for both 1D Dispatch and DispatchMesh operations.
The users need to install pre defined hardware and driver versions to access Agility SDK 1.619 and Shader Model 6.9.
- NVIDIA Driver version 595 or newer provides complete support for all RTX hardware. The hardware supports SER and OMM acceleration through all RTX products starting from the 40 series onward.
- AMD Adrenalin Edition 26.2.1. The Radeon RX 9000 series provides full support for SM 6.9 features.
- The Intel Arc B Series Graphics provide support for Windows operating system users.
The 1.719 preview SDK introduces Fence Barriers which serve developers who need more specific synchronization capabilities between GPU and CPU timeline operations. The system introduces a power efficient video processing path which enables tone mapping through VPblit 3DLUT while redirecting work from the main 3D engine. The feature currently operates on Intel Lunar Lake and Panther Lake along with the upcoming AMD 25.30 drivers.
