DirectX Tools and Documentation from NVIDIA

NVIDIA Graphics SDK
SDK 10
SDK 9

Popular Samples
Transparency AA
SLI Best Practices
Post-Processing with AA
GPU Cloth

Misc
GPU Device IDs

External Links
DirectX Homepage

Performance
PerfKit
PerfHUD
PerfSDK

ShaderPerf

Practical Perf. Analysis

Shader Authoring
FX Composer

DirectX 10
Coverage Sampling Antialiasing (CSAA)

Next Generation Effects in DirectX10

DX10 Performance and usage considerations

DirectX 9
Optimization for DirectX 9 Graphics

Shadowing Strategies for HLSL and FX Composer

Selected Developer Presentations

NVISION08: Introduction to the Direct3D 11 Graphics Pipeline; Easy Immersion with NVIDIA 3D Stereo
XNA Gamefest 2008: NVIDIA Graphics Performance and Authoring Tools for Direct3D 10; Tesselation of Displaced Subdivision Surfaces using Direct3D 11
GDC 2008: Advanced Visual Effects with Direct3D: Soft Shadow Mapping (3MB) (PDF); DirectX 10 Performance (200KB) (PDF); I nstanced Tesselation in DirectX 10 (4MB) (PDF); Harnessing the Power of Multiple GPUs (4MB) (PDF)
GDC 2007: NVIDIA FX Composer 2: A Comprehensive Shader Development Package; GPU Optimization with the Latest NVIDIA Performance Tools; Real-time volumetric smoke using D3D10; Soft shadows using hierarchical min-max shadow maps; How to make use of Direct3D10 now
CEDEC Tokyo 2006: State of the Art Cross-Platform Shader Development with FX; Introduction to DX10; DX10 Performance and usage considerations; Physics Simulation on NVIDIA GPUs
SIGGRAPH 2006: State of the Art Cross Platform Shader Development; Next Generation Effects in DirectX10; Optimize Your GPU with the Latest NVIDIA Performance Tools
Develop London 2006: Next Generation Games with Direct3D10
GDC 2006: DX10: Prepping your Engine for a Smooth Start; DX10: Batching and Performance Considerations; DX10: Practical Metaballs and Implicit surfaces

Want to Learn More? NVIDIA Documentation Home Page