diff --git a/Extension/Rendering/replay_export.cpp b/Extension/Rendering/replay_export.cpp
index 1248d279..95c01805 100644
--- a/Extension/Rendering/replay_export.cpp
+++ b/Extension/Rendering/replay_export.cpp
@@ -5,10 +5,16 @@
 #include "Engine/Game/Build/addresses.h"
 #include "Engine/Game/Build/20260929/replay_export.h"
 #include "Engine/Game/Build/supported_build.h"
+#include "Extension/UI/Overlay/gpu_diagnostics.h"
 #include <array>
 #include <atomic>
 #include <cstring>
+#include <vector>
 #include <Windows.h>
+#include <dxgi1_4.h>
+#include <wrl/client.h>
+#include <mfidl.h>
+#include <mftransform.h>
 
 namespace dingosdk::replay_export {
 namespace {
@@ -27,10 +33,71 @@ void submit(std::uintptr_t encoder, std::uintptr_t pixels, std::uintptr_t pitch,
         *reinterpret_cast<std::uint8_t*>(encoder + native::frame_permit) = 1;
     original.load()(encoder, pixels, pitch, unused);
 }
+
+// A hardware H.264 encoder only accepts frames from a device on its own GPU. On
+// a PC with two GPUs (an AMD processor's integrated graphics beside a graphics
+// card) the encoder the game gets first can belong to the GPU it does not render
+// on, and the export fails with "Failed to save video".
+using EnumTransforms = HRESULT(WINAPI*)(GUID, UINT32, const MFT_REGISTER_TYPE_INFO*, const MFT_REGISTER_TYPE_INFO*,
+    IMFActivate***, UINT32*);
+std::atomic<EnumTransforms> original_enum{};
+constexpr GUID video_encoder_category{0xf79eac7d, 0xe545, 0x4387, {0xbd, 0xee, 0xd6, 0x47, 0xd7, 0xbd, 0xe4, 0x2a}};
+constexpr GUID hardware_vendor_id{0x3aecb0cc, 0x035b, 0x4bcc, {0x81, 0x85, 0x2b, 0x8d, 0x55, 0x1e, 0xf3, 0xaf}};
+
+// The encoders do not say which adapter they sit on, only their vendor ("VEN_1002").
+UINT render_vendor() noexcept {
+    LUID render{};
+    if (!overlay::render_adapter_luid(render)) return 0;
+    Microsoft::WRL::ComPtr<IDXGIFactory4> factory;
+    Microsoft::WRL::ComPtr<IDXGIAdapter1> adapter;
+    DXGI_ADAPTER_DESC1 description{};
+    if (FAILED(CreateDXGIFactory1(IID_PPV_ARGS(&factory))) ||
+        FAILED(factory->EnumAdapterByLuid(render, IID_PPV_ARGS(&adapter))) || FAILED(adapter->GetDesc1(&description)))
+        return 0;
+    return description.VendorId;
+}
+
+HRESULT WINAPI enum_transforms(GUID category, UINT32 flags, const MFT_REGISTER_TYPE_INFO* input,
+    const MFT_REGISTER_TYPE_INFO* output, IMFActivate*** activates, UINT32* count) {
+    const HRESULT result = original_enum.load()(category, flags, input, output, activates, count);
+    if (FAILED(result) || !IsEqualGUID(category, video_encoder_category) || !activates || !*activates || !count)
+        return result;
+    const UINT wanted = render_vendor();
+    if (!wanted) return result;
+
+    std::vector<IMFActivate*> kept, dropped;
+    for (UINT32 i = 0; i < *count; ++i) {
+        IMFActivate* const activate = (*activates)[i];
+        wchar_t vendor[64]{};
+        UINT32 length{};
+        bool foreign{};
+        if (activate && SUCCEEDED(activate->GetString(hardware_vendor_id, vendor, 64, &length))) {
+            const wchar_t* const id = wcsstr(vendor, L"VEN_");
+            foreign = id && static_cast<UINT>(wcstoul(id + 4, nullptr, 16)) != wanted;
+        }
+        (foreign ? dropped : kept).push_back(activate);
+    }
+    if (dropped.empty() || kept.empty()) return result;
+    for (std::size_t i = 0; i < kept.size(); ++i) (*activates)[i] = kept[i];
+    *count = static_cast<UINT32>(kept.size());
+    for (auto* const activate : dropped) activate->Release();
+    logging::write(logging::Level::info, logging::Channel::graphics,
+        "Replay video export skipped hardware encoders that are not on the graphics card the game renders on.");
+    return result;
+}
 } // namespace
 
 bool start(std::uintptr_t base) noexcept {
     try {
+        if (const auto mfplat = LoadLibraryW(L"mfplat.dll")) {
+            void* const target = reinterpret_cast<void*>(GetProcAddress(mfplat, "MFTEnumEx"));
+            void* previous{};
+            if (target && hook_prepare(target, reinterpret_cast<void*>(&enum_transforms), &previous) == HookOk) {
+                original_enum = reinterpret_cast<EnumTransforms>(previous);
+                if (hook_enable(target) != HookOk) hook_remove(target);
+            }
+        }
+
         std::array<unsigned char, native::submit_frame_prefix.size()> bytes{};
         if (!base || !memory::read_bytes(base + native::submit_frame, bytes.data(), bytes.size()) ||
             bytes != native::submit_frame_prefix) {
diff --git a/Extension/Rendering/replay_export.h b/Extension/Rendering/replay_export.h
index 296ec215..8a907e55 100644
--- a/Extension/Rendering/replay_export.h
+++ b/Extension/Rendering/replay_export.h
@@ -7,5 +7,8 @@ namespace dingosdk::replay_export {
 // drops the rest. Rendering faster than it updates (an uncapped frame rate),
 // an export came out with a fraction of its frames and played that much too
 // fast. Every rendered frame of a replay export is encoded instead.
+// MP4 export on a PC with GPUs from two vendors (an AMD processor's integrated
+// graphics beside a graphics card) no longer picks the hardware encoder of the
+// GPU the game does not render on.
 bool start(std::uintptr_t base) noexcept;
 }
diff --git a/Extension/UI/Overlay/gpu_diagnostics.cpp b/Extension/UI/Overlay/gpu_diagnostics.cpp
index 3a4a6674..5dd51482 100644
--- a/Extension/UI/Overlay/gpu_diagnostics.cpp
+++ b/Extension/UI/Overlay/gpu_diagnostics.cpp
@@ -1068,9 +1068,25 @@ void watch_draws(ID3D12GraphicsCommandList* list) noexcept {
     SetLastError(error);
 }
 
+namespace {
+std::atomic<std::uint64_t> render_luid{};
+}
+
+bool render_adapter_luid(LUID& luid) noexcept {
+    const auto value = render_luid.load();
+    if (!value) return false;
+    luid.LowPart = static_cast<DWORD>(value);
+    luid.HighPart = static_cast<LONG>(value >> 32);
+    return true;
+}
+
 void record_gpu_identity(ID3D12Device* device) noexcept {
     static std::atomic<bool> recorded{};
     const auto error = GetLastError();
+    if (device) {
+        const auto luid = device->GetAdapterLuid();
+        render_luid = (static_cast<std::uint64_t>(static_cast<std::uint32_t>(luid.HighPart)) << 32) | luid.LowPart;
+    }
     try {
         ComPtr<IDXGIFactory4> factory;
         ComPtr<IDXGIAdapter1> adapter;
diff --git a/Extension/UI/Overlay/gpu_diagnostics.h b/Extension/UI/Overlay/gpu_diagnostics.h
index a5986ae6..3d148940 100644
--- a/Extension/UI/Overlay/gpu_diagnostics.h
+++ b/Extension/UI/Overlay/gpu_diagnostics.h
@@ -42,4 +42,6 @@ void watch_addresses(ID3D12GraphicsCommandList* list) noexcept;
 // The graphics card the game renders on and its driver's version: said in the log once, and kept
 // for crash reports' tags (crash_report::set_gpu). Always on.
 void record_gpu_identity(ID3D12Device* device) noexcept;
+// The adapter the game renders on, once record_gpu_identity has seen its device.
+bool render_adapter_luid(LUID& luid) noexcept;
 }