AMD FSR 4.1 DLL Leaks Online: RDNA 3 Users Already Testing AI Upscaling

A leaked DLL file from AMD's internal Vanguard driver testing has surfaced online, allowing RDNA 3 GPU owners to test the upcoming FSR 4.1 AI upscaling technology ahead of its official release—and early reports suggest noticeably sharper visuals compared to the current version.

Introduction: An Unexpected Leak

The gaming community was set abuzz on February 26, 2026, when a leaked AMD FSR 4.1 DLL file surfaced online, reportedly originating from AMD's internal Radeon Software "Vanguard" driver testing program. The leak has significant implications because FSR 4.1 was designed as an RDNA 4 exclusive feature, intended to showcase the AI acceleration capabilities of AMD's latest Radeon RX 9000 series graphics cards. However, resourceful users quickly discovered that the leaked DLL could be modified to work on older RDNA 3 hardware, challenging AMD's exclusivity positioning and raising questions about the true hardware requirements for AI-powered upscaling.

This leak represents the latest chapter in the ongoing evolution of AMD's FidelityFX Super Resolution technology, which has transformed from a spatial upscaling solution in its early iterations to a full-fledged machine learning-based platform that competes directly with Nvidia's industry-leading DLSS. The fact that RDNA 3 users can already test FSR 4.1—albeit through unofficial means—demonstrates the enthusiasm within the PC gaming community for accessible high-quality upscaling technology and the continued blurring of lines between hardware generations when it comes to feature support.

The timing of this leak is particularly noteworthy, coming just weeks after AMD officially launched its RDNA 4 architecture with the Radeon RX 9070 and RX 9070 XT graphics cards. These new GPUs were positioned as the exclusive home for FSR 4's AI-powered upscaling capabilities, giving AMD a competitive differentiator against Nvidia's RTX 50 series. The discovery that older hardware can potentially run the same technology complicates AMD's marketing narrative while simultaneously generating significant excitement among existing Radeon RX 7000 series owners who previously believed they would be left behind.

What Exactly Leaked: The FSR 4.1 DLL

The leaked file at the center of this story is named amdxcffx64.dll, a dynamic link library that users have identified as the core component responsible for FSR 4 and related driver-side functionality. This DLL appears to originate from an unreleased AMD Adrenalin driver that was being tested as part of AMD's Vanguard program—an internal testing initiative that gives select users early access to upcoming driver features and optimizations before public release. The version in question is reportedly labeled as FSR 4.1, suggesting it represents an incremental improvement over the FSR 4.0.3 that launched alongside RDNA 4.

What makes this DLL particularly interesting is that it contains the machine learning inference code that powers FSR 4's AI upscaling capabilities. Unlike previous versions of FSR that relied on shader-based spatial and temporal upscaling algorithms, FSR 4 leverages neural networks trained on high-resolution imagery to intelligently reconstruct details from lower-resolution renders. This AI-based approach requires hardware acceleration for the matrix multiplication operations that form the foundation of neural network inference—a capability that both RDNA 3 and RDNA 4 GPUs possess through their dedicated AI accelerator units.

The leak was first reported on Reddit's r/radeon community, where users shared details about the file and its origins. According to reports, the DLL was extracted from a Vanguard driver build and can be manually installed by replacing the existing amdxcffx64.dll file in the Windows System32 directory. Once installed, users report that the driver-level FSR 4 toggle in AMD's Adrenalin software can inject the upscaler into supported games, providing access to the newer technology without requiring official driver support for older hardware.

Leaked FSR 4.1 DLL Details

RDNA 3 Users Testing FSR 4.1: How It Works

The prospect of running FSR 4.1 on RDNA 3 hardware has generated considerable excitement among Radeon RX 7000 series owners, and early testing suggests that the technology is indeed functional on older GPUs—though not without some caveats. Users have reported success getting the leaked DLL to work on various RDNA 3 graphics cards, including the flagship RX 7900 XTX, the mid-range RX 7800 XT, and even older models like the RX 7700 XT. The process involves manually replacing the existing amdxcffx64.dll file in the Windows System32 directory and then enabling FSR 4 through AMD's Adrenalin software driver override feature.

The driver override capability in AMD's Adrenalin software is what makes this workaround possible. Similar to Nvidia's DLSS override feature, AMD allows users to force-enable FSR 4 in games that support FSR 3.1, even if the game doesn't natively support the newer version. Once the leaked DLL is installed, the driver toggle can inject FSR 4.1 into compatible games, allowing RDNA 3 users to experience the AI-powered upscaling that was originally marketed as an RDNA 4 exclusive. This injection method has become increasingly common as both AMD and Nvidia have moved toward driver-level feature overrides that don't require per-game developer implementation.

However, users should approach this workaround with appropriate caution. Installing leaked DLL files carries inherent security risks, as the files have not been validated by AMD and could potentially contain malicious code if obtained from untrustworthy sources. Additionally, using unsupported software configurations may cause stability issues, graphical artifacts, or other problems that could affect gameplay. AMD has not commented publicly on the leak or provided guidance for RDNA 3 users interested in FSR 4.1, leaving the community to experiment at their own risk without official support or documentation.

RDNA 3 GPUs Confirmed Working with FSR 4.1

• RX 7900 XTX: Flagship RDNA 3 card with full AI accelerator array
• RX 7900 XT: High-end variant confirmed functional
• RX 7900 GRE: Chinese market variant works with workaround
• RX 7800 XT: Mid-range model successfully tested
• RX 7700 XT: Lower-tier RDNA 3 confirmed operational
• RX 7600: Entry-level RDNA 3 may work but limited testing

Why FSR 4.1 Works on RDNA 3 Hardware

The ability of FSR 4.1 to function on RDNA 3 hardware is not entirely surprising when examining the technical capabilities of AMD's GPU architectures. RDNA 3, which powers the Radeon RX 7000 series launched in late 2022, introduced dedicated AI accelerators that AMD described as processors "optimized for 16-bit floating-point vector operations and dot4-based wave matrix multiply-and-accumulate operations." These AI accelerator units provide the computational horsepower necessary for running machine learning inference workloads—the same type of operations that power FSR 4's neural network-based upscaling.

While RDNA 4's second-generation AI accelerators offer improved performance compared to RDNA 3's first-generation implementation—reportedly doubling FP16 throughput and quadrupling INT8 matrix multiplication operations—the fundamental capability to accelerate neural network inference exists in both architectures. This hardware similarity means that, from a purely technical perspective, there is no absolute barrier preventing FSR 4 from running on RDNA 3 GPUs. The limitation appears to be primarily a product segmentation decision by AMD rather than a hard technical requirement, though performance optimization for the newer architecture may provide better results on RDNA 4 hardware.

The situation mirrors AMD's handling of FSR 3 frame generation, which was initially positioned as an RDNA 3 exclusive before eventually being made available on older RDNA 2 and even competing Nvidia GPUs. AMD has historically shown willingness to expand feature support to broader hardware audiences over time, suggesting that official RDNA 3 support for FSR 4 could potentially arrive in the future. The leak and subsequent community testing may even accelerate such a decision by demonstrating that the technology works acceptably on older hardware, removing one of the primary objections to broader support.

AI Accelerator Comparison: RDNA 3 vs RDNA 4

Early Reports: Sharper Visuals and Image Quality

Users who have tested the leaked FSR 4.1 DLL on RDNA 3 hardware are reporting encouraging results, with many noting noticeably sharper visuals compared to the current FSR 4.0.3 version. The improvements appear to focus on image clarity and detail reconstruction, addressing some of the softness and artifact issues that have characterized earlier FSR implementations. While comprehensive comparative analysis is still emerging from the community, the early consensus suggests that FSR 4.1 represents a meaningful step forward for AMD's upscaling technology, even when running on hardware it wasn't officially designed for.

Specific improvements noted by testers include better handling of fine details like text, foliage, and distant objects—areas where spatial upscalers have traditionally struggled compared to their AI-powered counterparts. The machine learning approach used in FSR 4 appears to be doing a better job of inferring detail that wasn't present in the original low-resolution render, producing images that more closely approximate native resolution quality. Some users have also reported reduced ghosting and temporal instability compared to FSR 3.1, though these improvements may vary depending on the specific game and settings used.

It's important to note that performance impact and image quality can vary significantly between RDNA 3 and RDNA 4 hardware. While the leaked DLL reportedly works on older GPUs, the AI accelerators in RDNA 4 are specifically optimized for the type of operations FSR 4.1 requires, potentially delivering better performance and quality on the newer architecture. RDNA 3 users may experience slightly higher performance overhead or marginally different image quality compared to official RDNA 4 implementations, though detailed comparative testing is still ongoing within the community.

Reported FSR 4.1 Improvements Over FSR 4.0.3

• Sharper Image Quality: Noticeable improvement in overall clarity and detail
• Better Fine Detail: Improved rendering of text, foliage, and distant objects
• Reduced Ghosting: Less temporal artifacts in motion-heavy scenes
• Enhanced Stability: Fewer flickering or shimmering issues
• Edge Quality: Cleaner edges with less pixelation or blurring
• Detail Reconstruction: Better inference of missing details from low-res source

FSR 4 Overview: AMD's AI Upscaling Evolution

FSR 4, codenamed "Redstone" during development, represents AMD's most significant advancement in upscaling technology and marks the company's transition from spatial-temporal algorithms to full machine learning-based upscaling. Announced alongside the RDNA 4 architecture in early 2025, FSR 4 leverages the AI accelerators present in Radeon RX 9000 series GPUs to perform neural network inference that reconstructs high-quality images from lower-resolution renders. This approach fundamentally differs from previous FSR versions, which relied on shader-based spatial upscaling combined with temporal data accumulation to improve image quality.

The transition to AI-based upscaling brings AMD more directly into competition with Nvidia's DLSS technology, which has used machine learning since its introduction in 2019. Nvidia's years of experience with neural network upscaling have allowed the company to refine its algorithms and training data, resulting in consistently high image quality that has set the industry standard. AMD's entry into this space with FSR 4 represents the company's most serious attempt to match Nvidia's quality while maintaining the broader platform flexibility that has characterized the FSR brand—though the current RDNA 4 exclusivity limits that flexibility compared to previous versions.

FSR 4 also includes a suite of related technologies that AMD has branded under the Redstone umbrella. Beyond upscaling, the package includes AI-powered frame generation, ray reconstruction for improved ray tracing visuals, and radiance caching for more efficient global illumination. These features mirror capabilities Nvidia has developed for DLSS 3 and 4, indicating AMD's commitment to feature parity with its primary competitor. At launch, AMD reported that FSR 4 upscaling was supported in 205 games, with AI frame generation available in 32 titles—numbers that have grown rapidly as developers adopt the newer SDK.

FSR Technology Evolution

The RDNA 4 Exclusive Strategy

AMD's decision to launch FSR 4 as an RDNA 4 exclusive feature reflects a strategic shift from the company's traditional approach of making FSR available across a wide range of hardware, including competing Nvidia GPUs. This exclusivity serves multiple purposes from AMD's perspective: it provides a compelling reason for gamers to upgrade to the new Radeon RX 9000 series, differentiates RDNA 4 from the previous generation in a meaningful way, and positions AMD's latest GPUs as technologically competitive with Nvidia's RTX offerings. The strategy mirrors Nvidia's approach with DLSS, which has always been exclusive to RTX hardware.

The RDNA 4 architecture introduces significant improvements to AI processing capabilities that AMD has emphasized as enabling FSR 4's functionality. The second-generation AI accelerators deliver substantially higher throughput for the matrix operations that neural network inference requires, theoretically allowing FSR 4 to run with minimal performance overhead while maintaining high image quality. AMD has claimed that FSR 4 can deliver up to 3.7x performance improvement in supported games, a figure that demonstrates the potential of AI upscaling to transform the gaming experience on supported hardware.

However, the leak of FSR 4.1 and its apparent functionality on RDNA 3 hardware has complicated this exclusive positioning. If the technology works acceptably on older hardware, the artificial restriction becomes more apparent to consumers, potentially generating frustration among Radeon RX 7000 series owners who feel they've been unnecessarily excluded from features their hardware can technically support. AMD may face pressure to officially expand FSR 4 support to RDNA 3, though such a decision would remove one of the primary differentiators for the company's latest GPU generation.

FSR 4.1 vs DLSS 4.5: How Do They Compare?

The battle between AMD's FSR and Nvidia's DLSS has defined the upscaling conversation for years, and the latest versions of both technologies continue this competition with increasingly sophisticated approaches. Nvidia's DLSS 4.5 represents the latest refinement of a technology that has been machine learning-based since its inception, benefiting from years of training data refinement and algorithm optimization. AMD's FSR 4.1 is newer to the AI approach but has made impressive strides in image quality, as the leaked testing on RDNA 3 hardware demonstrates. Understanding how these technologies compare helps gamers make informed decisions about their hardware choices.

In terms of image quality, recent blind tests have shown that nearly half of PC gamers prefer DLSS 4.5 over FSR 4 and even native rendering in many scenarios. DLSS has historically excelled at handling motion, with fewer ghosting artifacts and better temporal stability in fast-moving scenes. However, FSR 4 has narrowed the gap significantly compared to previous versions, with the leaked FSR 4.1 reportedly offering further improvements in sharpness and detail reconstruction. The gap between the two technologies, while still measurable, has become much smaller as AMD has refined its machine learning approach.

The broader consideration for many gamers remains platform compatibility. DLSS remains exclusive to Nvidia RTX hardware, while previous FSR versions have been available on virtually any GPU—including Nvidia cards. FSR 4's RDNA 4 exclusivity has somewhat complicated this narrative, though the leak suggests that the hardware requirements may be less strict than AMD has publicly indicated. For gamers considering a GPU purchase, the choice between DLSS and FSR increasingly comes down to overall platform preference rather than upscaling quality alone, as both technologies have reached a level of maturity that makes either a viable option for most users.

FSR 4.1 vs DLSS 4.5 Feature Comparison

What This Means for AMD's Strategy

The leak of FSR 4.1 and its successful testing on RDNA 3 hardware places AMD in an interesting strategic position. On one hand, the company has invested significantly in positioning FSR 4 as an RDNA 4 exclusive feature that demonstrates the value of upgrading to the latest GPU generation. On the other hand, community experimentation has shown that the technology can function on older hardware, potentially creating demand from Radeon RX 7000 series owners for official support. How AMD responds to this situation could have implications for the company's relationship with its existing customer base.

Historically, AMD has shown willingness to expand feature support beyond initially announced hardware requirements. FSR 3's frame generation was eventually made available on RDNA 2 and competing GPUs, and the company has generally positioned FSR as a broadly accessible technology that benefits the entire gaming ecosystem. However, FSR 4's machine learning approach provides a more compelling reason for hardware exclusivity, as the AI accelerators in RDNA 4 offer genuine performance advantages for neural network inference. The decision AMD faces is whether the marketing value of exclusivity outweighs the potential goodwill from supporting existing customers.

The situation also raises questions about AMD's product segmentation strategy going forward. If FSR 4.1 can run effectively on RDNA 3 hardware, what other features might be artificially restricted for marketing purposes? And conversely, does this leak suggest that AMD's AI accelerator technology has been more capable than initially utilized, potentially opening the door to more AI-powered features on existing hardware? The answers to these questions will shape how consumers perceive AMD's hardware roadmap and the longevity of features on their purchased products.

Technical Details: How Users Are Installing FSR 4.1

For technically inclined users interested in experimenting with the leaked FSR 4.1 DLL, the installation process is relatively straightforward but comes with important caveats. The procedure involves navigating to the Windows System32 directory, locating the existing amdxcffx64.dll file, and replacing it with the leaked version. After replacement, users can enable FSR 4 through the driver-level toggle in AMD's Adrenalin software, which will inject the upscaler into games that support FSR 3.1 or later. This driver override approach eliminates the need for per-game patches or developer implementation, making the feature accessible across a wide library of supported titles.

However, this process involves modifying system files and using unauthorized software, which carries inherent risks. Users should create system restore points before making any changes and understand that AMD does not provide support for this configuration. There's also the security consideration of installing DLL files obtained from unofficial sources—malicious actors could potentially distribute compromised versions that contain malware or other harmful code. Anyone considering this modification should verify the file's authenticity through community channels and use appropriate security precautions.

Additionally, performance and image quality may not match what RDNA 4 users experience with officially supported FSR 4.1. The AI accelerators in RDNA 4 are specifically optimized for the inference workloads FSR 4 requires, and the leaked DLL may not be fully optimized for RDNA 3's hardware configuration. Users may encounter higher performance overhead, different image quality characteristics, or stability issues that wouldn't be present with officially supported configurations. These trade-offs should be weighed against the benefit of accessing newer upscaling technology on older hardware.

Installation Steps (For Informational Purposes)

1. Create System Restore Point: Backup your system before making changes
2. Locate Existing DLL: Navigate to C:\Windows\System32 and find amdxcffx64.dll
3. Backup Original: Rename or copy the original file as a backup
4. Install Leaked DLL: Copy the FSR 4.1 version to System32
5. Enable in Adrenalin: Open AMD Adrenalin and enable FSR 4 override
6. Test in Games: Launch supported games and verify FSR 4.1 is active

Warning: This process involves modifying system files with unauthorized software. Proceed at your own risk and verify file authenticity from trusted community sources.

Frequently Asked Questions

Conclusion

The leak of AMD's FSR 4.1 DLL and its successful deployment on RDNA 3 hardware represents a fascinating intersection of corporate strategy, technical capability, and community experimentation. The situation demonstrates that AMD's AI accelerator technology has been more capable than initially utilized, and the artificial restriction of FSR 4 to RDNA 4 hardware has been at least partially exposed as a marketing decision rather than a hard technical requirement. For Radeon RX 7000 series owners, this leak offers an intriguing opportunity to experience the latest upscaling technology, albeit through unofficial and unsupported means.

The broader implications for AMD's product strategy remain to be seen. The company could choose to officially support FSR 4 on RDNA 3, generating goodwill among existing customers but potentially reducing one of the key differentiators for its latest GPU generation. Alternatively, AMD could maintain exclusivity and accept the community frustration that comes from knowing older hardware is technically capable of running features it's officially denied. The decision AMD makes will reveal much about how the company views its relationship with existing customers versus its need to drive upgrades to new hardware.

For the gaming community, the FSR 4.1 leak serves as another reminder of the rapid evolution of upscaling technology and the increasing importance of AI acceleration in modern GPUs. As both AMD and Nvidia continue to refine their approaches to machine learning-based image reconstruction, gamers benefit from increasingly sophisticated tools that make high-fidelity gaming more accessible across a wider range of hardware. Whether through official support or community workarounds, the expansion of AI upscaling technology ultimately serves the interests of gamers who want the best possible visual experience without requiring the absolute latest hardware.