KB5128773 moves AMD's Vitis AI provider to 2.2609.1.0
Microsoft's support article describes the component as an execution provider used with ONNX Runtime / Windows machine learning that enables hardware-accelerated AI inference on AMD platforms. The release note also explains that Vitis AI is AMD's development stack for hardware-accelerated AI inference, and it targets AMD platforms including Ryzen AI, AMD Adaptable SoCs, and Alveo Data Center Acceleration Cards.
That platform list describes AMD's whole Vitis AI stack. It does not say which machines get this package. The KB's stated scope is Windows 11 24H2 and 25H2. Whether a given PC actually installs and uses the provider depends on its hardware and drivers, which are covered below.
Here are the basic facts from Microsoft's KB article:
| Item | Detail |
|---|---|
| KB number | KB5128773 |
| Component version | 2.2609.1.0 |
| Released | September 22, 2026 |
| Applies to | Windows 11 version 24H2 and 25H2, all editions |
| Delivery | Automatic via Windows Update |
| Prerequisite | Latest cumulative update for 24H2 or 25H2 |
| Replaces | KB5121773 (version 2.2607.3.0, released July 28, 2026) |
| Update history entry | Windows Runtime ML AMD NPU Execution Provider Update (KB5128773) |
The release note does not name any fixes, performance figures, new operators, or security changes. Nothing in it suggests a security patch or a fix for a known problem, and none should be assumed.
How execution providers work in Windows ML
In Windows ML, an execution provider (EP) is the hardware-specific backend that ONNX Runtime uses to run a model. Microsoft's developer documentation says Windows ML ships with two providers built in: CPU and the older DirectML. Vendor providers are downloaded on demand. These include AMD's VitisAI, Intel's OpenVINO, Qualcomm's QNN, NVIDIA's NvTensorRtRtx, and AMD's separate MIGraphX provider for GPUs. The Vitis AI provider is registered as VitisAIExecutionProvider, and AMD is listed as the vendor.
With this design, an app developer writes against one runtime. The work of targeting a particular chip is handed to a component the silicon vendor maintains, and Windows Update can service that component separately from the app. Microsoft's documentation says the downloadable providers work on Windows 11 24H2 (build 26100) or later, "depending on device and driver compatibility." Apps get them through the Windows ML ExecutionProviderCatalog APIs.
The names are a common source of confusion. The KB title calls the package the "AMD Vitis AI Execution Provider," but Update history lists it as "Windows Runtime ML AMD NPU Execution Provider Update." Both names refer to the same package. Admins looking for it in update reports should search for the KB number or the "AMD NPU Execution Provider" wording, not "Vitis."
Windows Update services the provider, and apps can't choose the version
Microsoft's guidance on updating execution providers covers the whole EP category, not just this release. Once a provider is installed on a device, it is updated through Windows Update's optional non-security preview releases, often called "D week" releases. KB5128773 fits that pattern: it came out on the fourth Tuesday of September, alongside the rest of that month's execution-provider packages.
According to the same guidance, these compatible updates reach apps automatically, without any change to the app. That is how apps can pick up performance improvements and support for new operators. Microsoft also says there is currently no way for an app to install an updated EP programmatically. Windows Update handles it.
This has two consequences for developers shipping Windows ML apps on AMD hardware:
- The provider version on a customer's machine can change under a shipped app without the app being updated.
- A developer can't bundle or force a specific VitisAI build through the Windows ML catalog.
If an app's behavior on AMD NPUs changes after late September, check the installed provider version before anything else. Microsoft's release note doesn't say whether this release changes operator support or performance, so it gives developers no reason to expect a difference either way.
AMD driver limits determine whether the provider is used
The KB lists only Windows versions. Hardware limits are in Microsoft's Windows ML provider documentation, which was last updated September 21, 2026. It gives this driver range for VitisAI:
- Minimum: AMD Adrenalin Edition 25.6.3 with NPU driver 32.00.0203.280
- Maximum: AMD Adrenalin Edition 25.9.1 with NPU driver 32.00.0203.297
The documentation doesn't link that range to version 2.2609.1.0 specifically. Read it as the current published requirement for the VitisAI provider, not as a promise about this package. Still, a published maximum is worth noting. On a machine running a newer AMD driver than the documented ceiling, the provider may fall outside the supported configuration. For a Ryzen AI PC where local AI features aren't using the NPU, the driver version is the first thing to check. The Windows build is less likely to be the cause.
On the other platforms in the Vitis AI list, AMD Adaptable SoCs and Alveo data center cards are part of AMD's broader stack. Nothing in Microsoft's servicing material suggests this Windows Update package targets them.
The monthly release history behind KB5128773
KB5128773 is one of a steady series of AMD provider packages. Early releases carried Windows ML 1.8.x version numbers. KB5068002, version 1.8.25.0, includes improvements to the AMD Vitis AI Execution Provider for Windows 11, version 24H2. Its release note says it does not replace any previously released update. Later packages added 25H2. KB5077529, version 1.8.50.0, replaces the previously released update KB5068002. KB5079258, version 1.8.53.0, replaces the previously released update KB5077529.
The versions then moved to a 2.x scheme that encodes the year and month. KB5096134 (version 2.2605.2.0) replaces the previously released update KB5089169. KB5103226 (version 2.2606.1.0) in turn replaces the previously released update KB5096134. The July package KB5121773, version 2.2607.3.0, is the predecessor KB5128773 names directly. WindowsForum readers may also have seen separate packages for Windows 11 26H1. KB5079260, for example, includes improvements to the AMD Vitis AI Execution Provider AI component for Windows 11, version 26H1. KB5128773 does not list 26H1, so those devices are on a separate track.
Microsoft's AI components release history lists ten execution-provider packages for September 22, 2026, with KB numbers from KB5128773 to KB5128782 and versions 2.2609.1.0, 2.2609.2.0, and 2.2609.3.0. Several vendors publish packages on the same day, so KB5128773 covers only the AMD Vitis AI package. Microsoft files these under AI components "used on Copilot+ PCs," along with Phi Silica and the image-processing models.
Every release note in this series carries the same one-line description, "includes improvements." Admins shouldn't expect changelogs for these packages. Watching the version numbers and KB supersedence is the practical way to track them.
What this means for you
Most people don't need to do anything, apart from checking that the prerequisite cumulative update is installed.
For home users on AMD Ryzen AI laptops running Windows 11 24H2 or 25H2, KB5128773 arrives automatically once the device has the latest cumulative update. It isn't an optional download to hunt for. On PCs without a compatible AMD NPU and driver, it has little practical effect on AI features.
For admins, Microsoft's KB offers no separate manual-download or deployment instructions and no troubleshooting steps. The documented check is simple. Keep devices current on the monthly cumulative update, then confirm the package in Update history. If a device doesn't offer it, look at the cumulative-update level and the AMD driver version before assuming something has failed.
To verify on a device:
- Confirm the device runs Windows 11 version 24H2 or 25H2 and has the latest cumulative update installed.
- Open Settings > Windows Update > Update history.
- Look for "Windows Runtime ML AMD NPU Execution Provider Update (KB5128773)." If it's listed, the update is installed.
Key takeaways:
- KB5128773 updates the AMD Vitis AI Execution Provider to version 2.2609.1.0 on Windows 11 24H2 and 25H2, and it replaces KB5121773 (2.2607.3.0).
- Windows Update installs it automatically. The only prerequisite Microsoft states is the latest cumulative update for 24H2 or 25H2.
- In Update history, the package appears as the "Windows Runtime ML AMD NPU Execution Provider Update," not under the Vitis AI name.
- Microsoft describes the contents only as "improvements." Don't treat the update as a security fix or a measured performance gain.
- The current VitisAI requirement is AMD Adrenalin 25.6.3 (NPU driver 32.00.0203.280) through Adrenalin 25.9.1 (NPU driver 32.00.0203.297), so check drivers on any NPU that isn't being used.
- Developers using Windows ML can't pin or programmatically install a provider version, so they should record the EP version when diagnosing behavior changes on AMD hardware.
KB5128773 is routine servicing. Microsoft maintains AMD's NPU backend as its own Windows component, and that component has now been updated every month for about a year, with a new version shipping during each month's optional non-security preview update. Admins can expect the next AMD Vitis AI package to replace KB5128773 in a future cycle, most likely around October's non-security preview update, and Windows Update will install it the same way.