DXVK-NVAPI 0.9.1 Lands With Critical Game Fixes and New DLSS Override

The DXVK-NVAPI project, a critical component of Valve's Steam Play (Proton) stack that enables NVIDIA's proprietary features like DLSS and Reflex in Windows games on Linux, has been updated to version 0.9.1. This release focuses on compatibility fixes for several problematic titles and introduces a new user-controllable override for DLSS scaling ratios.

For users running NVIDIA GPUs on Linux, DXVK-NVAPI is the bridge that translates Windows-specific NVIDIA API calls into Vulkan, allowing games to access features like Deep Learning Super Sampling (DLSS), NVIDIA Reflex, and PhysX. Without it, many modern games either fail to launch or run with reduced visual fidelity and performance. The 0.9.1 update, released on January 24, 2026, addresses several long-standing issues that have plagued specific titles.

New DLSS Scaling Override

A notable addition in this release is the introduction of new Direct Rendering Settings (DRS) environment variables. These allow users to manually override the DLSS Super Resolution (SR) and Ray Reconstruction (RR) scaling ratios. This is particularly useful for enthusiasts who want to fine-tune the performance-to-quality balance beyond the game's built-in presets. The implementation is documented in the project's "Passing driver settings" guide, giving users direct control over this critical DLSS parameter.

Critical Game-Specific Workarounds

The bulk of the 0.9.1 release notes detail compatibility fixes for several demanding titles:

• DOOM: The Dark Ages: A workaround was added to fake successful calls to the Reflex API when DXVK-NVAPI's Vulkan Reflex layer isn't installed. This resolves a specific issue where the game would display a persistent pink tint, a common symptom of failed API translation.

• Godot Engine Titles: To prevent crashes at startup for games built with the Godot engine, several DRS functions have been implemented as stubs. This ensures the engine's API queries receive a valid response, even if the underlying functionality isn't fully implemented.

• The Last of Us Part 2: A clever workaround was implemented for this title. The game was modified to let several GPU queries return a success status, even when no real data is available. This allows the game to start correctly when it detects that NVAPI is present on the system.

• Middle-earth: Shadow of Mordor: A startup crash was fixed by properly implementing the NvAPI_D3D1x_Present function, which is essential for the game's rendering pipeline.

• Stormgate: To prevent a crash when opening the in-game map editor, DXVK-NVAPI now reports that Reflex is unavailable for this specific title, avoiding a faulty API call.

Under-the-Hood Improvements

Beyond game-specific fixes, version 0.9.1 includes several internal enhancements. The Vulkan layer logging has been improved, providing better diagnostic information for developers and power users troubleshooting compatibility issues. The project has also been re-based against newer headers: the NVIDIA R590 driver headers, updated Vulkan headers, and the latest upstream DirectX headers. This ensures better forward compatibility with newer drivers and APIs.

Integration and Availability

These changes are now available in the DXVK-NVAPI 0.9.1 release on GitHub. The fixes and enhancements will likely be integrated into an upcoming Valve Steam Play Proton update, bringing these improvements to the broader Linux gaming community automatically. For users who prefer manual updates or are testing specific compatibility, building from source remains an option.

This release underscores the ongoing, meticulous work required to maintain feature parity between Windows and Linux gaming. Each game presents unique challenges, and the DXVK-NVAPI project serves as a vital, ever-evolving patchwork that ensures NVIDIA's premium features work seamlessly on open-source platforms.