--- title: "OptiScaler FSR4 guide | OptiScaler" description: "Learn how OptiScaler FSR4 support works, why hardware and driver requirements matter, how fallback can occur, and what to verify before tuning." canonical: https://optiscaler.ink/guides/fsr4-compatibility-and-fallback updated: 2026-10-18 --- # OptiScaler FSR4 guide: compatibility, INT8 and fallback checks Learn how OptiScaler FSR4 support works, why hardware and driver requirements matter, how fallback can occur, and what to verify before tuning. ## Facts (2026-10-18) - **Version:** OptiScaler 0.9.4 (reference build, July 2026) - **APIs:** DirectX 11, DirectX 12, Vulkan - **Upscalers:** DLSS, FSR and XeSS inputs/outputs where compatible - **Frame generation:** Experimental OptiFG (DirectX 12) - **Overlay:** Insert key - **Install:** ZIP extracted next to the main game executable - **Platform:** Windows; Linux via Proton/Wine varies - **Site:** Independent guide — not the official project site ## In short Learn how OptiScaler FSR4 support works, why hardware and driver requirements matter, how fallback can occur, and what to verify before tuning. ## Steps 1. Check the output path, GPU capability and driver/SDK behaviour for FSR4. 2. Select the FSR4 output in the overlay where it is offered. 3. Verify with the OptiScaler status or watermark indicator that FSR4, not a fallback, is active. 4. If the hardware is unsupported, expect another output path instead. ## Facts that do not change Reference build is OptiScaler 0.9.4. Install is a ZIP next to the main game executable; the overlay opens with Insert. Avoid online or anti-cheat protected games, and test offline first. ## FSR4: related searches - [OptiScaler FSR4](https://optiscaler.ink/keywords/optiscaler-fsr4) - [OptiScaler FSR 4](https://optiscaler.ink/keywords/optiscaler-fsr-4) - [OptiScaler FSR4 Guide](https://optiscaler.ink/keywords/optiscaler-fsr4-guide) - [OptiScaler FSR4 Support](https://optiscaler.ink/keywords/optiscaler-fsr4-support) - [How to Enable FSR4 with OptiScaler](https://optiscaler.ink/keywords/how-to-enable-fsr4-with-optiscaler) - [OptiScaler FSR4 Not Working](https://optiscaler.ink/keywords/optiscaler-fsr4-not-working) - [OptiScaler FSR4 INT8](https://optiscaler.ink/keywords/optiscaler-fsr4-int8) - [OptiScaler FSR4 Fallback](https://optiscaler.ink/keywords/optiscaler-fsr4-fallback) - [Why Does OptiScaler FSR4 Fall Back?](https://optiscaler.ink/keywords/why-does-optiscaler-fsr4-fall-back) - [OptiScaler FSR4 Requirements](https://optiscaler.ink/keywords/optiscaler-fsr4-requirements) - [OptiScaler FSR4 Hardware Requirements](https://optiscaler.ink/keywords/optiscaler-fsr4-hardware-requirements) - [OptiScaler FSR4 Older GPU](https://optiscaler.ink/keywords/optiscaler-fsr4-older-gpu) - [OptiScaler FSR4 Driver SDK](https://optiscaler.ink/keywords/optiscaler-fsr4-driver-sdk) - [How to Check FSR4 Is Active OptiScaler](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler) - [How to Tell If OptiScaler FSR4 Is Really Active](https://optiscaler.ink/keywords/how-to-tell-if-optiscaler-fsr4-is-really-active) - [OptiScaler FSR4 Watermark](https://optiscaler.ink/keywords/optiscaler-fsr4-watermark) - [OptiScaler FSR4 Status Indicator](https://optiscaler.ink/keywords/optiscaler-fsr4-status-indicator) - [OptiScaler FSR4 Quality](https://optiscaler.ink/keywords/optiscaler-fsr4-quality) - [OptiScaler FSR4 Artifacts](https://optiscaler.ink/keywords/optiscaler-fsr4-artifacts) - [OptiScaler FSR 4.1.1](https://optiscaler.ink/keywords/optiscaler-fsr-4-1-1) - [OptiScaler FFX 2.3](https://optiscaler.ink/keywords/optiscaler-ffx-2-3) - [OptiScaler DLSS to FSR4](https://optiscaler.ink/keywords/optiscaler-dlss-to-fsr4) - [How to Check FSR4 Is Active OptiScaler 0.9.4](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler-0-9-4) - [How to Enable FSR4 with OptiScaler 0.9.4](https://optiscaler.ink/keywords/how-to-enable-fsr4-with-optiscaler-0-9-4) - [How to Check FSR4 Is Active OptiScaler Linux](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler-linux) - [How to Enable FSR4 with OptiScaler Linux](https://optiscaler.ink/keywords/how-to-enable-fsr4-with-optiscaler-linux) - [Why Does OptiScaler FSR4 Fall Back 0.9.4?](https://optiscaler.ink/keywords/why-does-optiscaler-fsr4-fall-back-0-9-4) - [How to Check FSR4 Is Active OptiScaler 2026](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler-2026) - [How to Check FSR4 Is Active OptiScaler Reddit](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler-reddit) - [How to Check FSR4 Is Active OptiScaler Tutorial](https://optiscaler.ink/keywords/how-to-check-fsr4-is-active-optiscaler-tutorial) - [How to Enable FSR4 with OptiScaler 2026](https://optiscaler.ink/keywords/how-to-enable-fsr4-with-optiscaler-2026) - [How to Enable FSR4 with OptiScaler Reddit](https://optiscaler.ink/keywords/how-to-enable-fsr4-with-optiscaler-reddit) ## FAQ ### What is OptiScaler? OptiScaler is a community tool that can intercept supported in-game upscaler calls and redirect them to another supported upscaling backend, with additional tuning options. ### How does OptiScaler work in a game? The game exposes an input upscaler, OptiScaler sits between the game and the selected output backend, and the chosen output handles the final upscaling path where compatibility allows. ### Does OptiScaler support DirectX 11? Yes, DirectX 11 is supported, although the available output methods and behavior can differ from DirectX 12. ### Does OptiScaler support DirectX 12? Yes. DirectX 12 has broad support and is also the API used by experimental OptiFG functionality. ## Related - [OptiScaler guides: install, FSR4, Linux, performance and safety](https://optiscaler.ink/guides) - [OptiScaler FAQ: the official 20 questions, answered](https://optiscaler.ink/faq) - [OptiScaler install guide: clean setup from start to finish](https://optiscaler.ink/guides/install-optiscaler-clean-setup) - [How OptiScaler works: input, output and overlay explained](https://optiscaler.ink/guides/how-optiscaler-works-input-output) - [OptiScaler compatibility guide for DirectX 11, DirectX 12 and Vulkan](https://optiscaler.ink/guides/compatibility-dx11-dx12-vulkan) ## Download ZIP next to the game executable: [Download OptiScaler](https://optiscaler.ink/download) Markdown mirror: https://optiscaler.ink/guides/fsr4-compatibility-and-fallback.md