High-performance video recording & streaming for AMD Radeon. Gaming unleashed.
~85% less RAM than stock OBS. Fixes AMD bitrate spikes. Built for gamers.
Download • Features • Performance • AMD Fixes • Building
RDNA Cast is an independent open-source project. It is not affiliated with, endorsed by, or sponsored by Advanced Micro Devices, Inc. or the OBS Project. "AMD", "Radeon", and "RDNA" are trademarks of Advanced Micro Devices, Inc., used here only descriptively to indicate target hardware compatibility.
RDNA Cast is a fork of OBS Studio, redistributed under the GNU General Public License v2.0. See COPYING for the full GPL text and THIRD_PARTY_LICENSES.md for bundled-library licenses.
RDNA Cast is a lightweight fork of OBS Studio 31.0.3, built exclusively for AMD hardware on Windows. It strips out everything you don't need, optimizes what's left for AMD Zen 3+ CPUs and RDNA GPUs, and fixes real AMD encoder bugs that cause bitrate spikes and drops during streaming.
| Metric | Stock OBS 31.0.3 | RDNA Cast |
|---|---|---|
| RAM (idle) | ~300-400 MB | ~52 MB |
| Threads | ~50-60 | ~15 |
| Plugin DLLs | ~30+ | 12 |
| Disk size | ~500+ MB | 139 MB (installer) |
| Preview GPU load | Full refresh rate (165 FPS) | ~40 FPS (throttled) |
| Gaming FPS impact | 20-30 FPS loss reported | Significantly reduced |
- AMD-first encoder defaults — AMF HEVC is the default encoder. Dropdown: AMD AV1 > HEVC > H.264 > x264 fallback
- 11 plugins instead of 36 — only what you need for streaming and recording
- AVX2 + /favor:AMD64 compiler optimizations — built for Zen 3+ instruction scheduling
- D3D11-only rendering — AMD's best-optimized driver path on Windows
- Preview throttled to ~40 FPS — GPU renders preview every 4th frame instead of 165 FPS. Encoder still gets every frame at full quality
- Pre-analysis disabled — eliminates the AMF pre-encode pass that steals GPU cycles from your game
- Reduced GPU encode textures (10 → 6) — frees VRAM for game textures
- Reduced async frame cache (30 → 12) — less memory pressure
- No profiler overhead in the render loop
- Portable by default — settings, scenes, profiles live next to the executable
- Close-to-tray — X minimizes to system tray (like Steam/AMD Adrenalin). Recording keeps running
- Tray controls — right-click for Stream, Record, Replay Buffer, Save Replay, Exit
- GitHub Releases updates — Help → GitHub Releases opens the official release page for installers
- About dialog with GPLv2-or-later, MIT additions, and bundled-library notices
- Windows installer with custom branding via Inno Setup
These fixes address long-standing AMD AMF issues reported across OBS #12013, OBS #12512, AMF #465, and AMF #323:
| Fix | Problem | Solution |
|---|---|---|
| AV1 filler data bug | Stock OBS compares AV1 rate control against H.264 enum constants — filler data never activates for AV1 CBR. Causes bitrate drops to 0 on static scenes. | Use correct AMF_VIDEO_ENCODER_AV1_RATE_CONTROL_METHOD_CBR enum |
| VBV buffer too large | Stock OBS sets VBV = 1 full second of bitrate, allowing spikes up to ~2x target before correction | VBV = 500ms (bitrate / 2) — cuts maximum spike in half |
| Startup encoder overload | H.264 pre-analysis (PREENCODE_ENABLE) consumes first GOP, causing 2-3 second frame drops at stream start |
Pre-analysis disabled |
| HQCBR filler data | High Quality CBR mode didn't enable filler data on any codec | Filler data now enabled for both CBR and HQCBR on H.264, HEVC, and AV1 |
| Component | Tested On |
|---|---|
| CPU | AMD Ryzen 7 5700X3D (Zen 3, 8C/16T) |
| GPU | AMD Radeon RX 9070 XT (RDNA 4) |
| RAM | 32GB DDR4 |
| OS | Windows 11 Pro |
Any AMD system with a Zen 2+ CPU and RDNA+ GPU should work. AVX2 required (all Zen CPUs support this).
obs-nvenc— NVIDIA GPU encoderobs-qsv11— Intel Quick Sync Videonv-filters— NVIDIA GPU filters
libobs-opengl,libobs-metal, all macOS/Linux/BSD plugins
obs-browser— Chromium (can be re-enabled with-DENABLE_BROWSER=ON)obs-websocket,obs-webrtc,vlc-video,decklink,aja,obs-vst,text-freetype2,obs-libfdk- Lua/Python scripting, frontend-tools plugin
| Plugin | Purpose |
|---|---|
obs-ffmpeg |
FFmpeg muxing + AMF hardware encoder (H.264, HEVC, AV1) |
obs-x264 |
Software H.264 fallback |
obs-filters |
Video/audio filters |
obs-transitions |
Scene transitions |
obs-outputs |
RTMP, SRT, RIST streaming + recording |
obs-text |
Windows text rendering |
image-source |
Image/slideshow sources |
rtmp-services |
Streaming service configs (Twitch, YouTube, etc.) |
win-capture |
Window, game, and monitor capture |
win-dshow |
Webcams and capture cards (DirectShow) |
win-wasapi |
Windows audio capture/output |
- Visual Studio 2022 (Community or BuildTools) with Desktop development with C++ workload + ATL
- CMake 3.28+
- Git
- Inno Setup 6 (for installer, optional)
git clone https://github.com/gkaragioul/RDNA_Cast.git
cd RDNA_Cast
cmake --preset amd-lite-x64
cmake --build build_amd_lite --config RelWithDebInfo --parallelcmake --preset amd-lite-x64 -DENABLE_BROWSER=ON -DENABLE_WEBSOCKET=ON
cmake --build build_amd_lite --config RelWithDebInfo --parallelRun build.bat — handles CMake configure, build, and Inno Setup packaging in one step.
All RDNA Cast changes are gated behind the OBS_AMD_LITE CMake flag and #ifdef OBS_AMD_LITE preprocessor guards. Building without the flag produces stock OBS Studio. This makes upstream merges from obsproject/obs-studio straightforward.
- OBS Studio by the OBS Project — the foundation this project is built on
- AMD AMF SDK — hardware encoding interface
- All upstream OBS contributors listed in AUTHORS
If you use RDNA Cast and want to support the upstream project that makes it possible, please contribute to OBS Studio.
RDNA Cast is an OBS Studio fork. The combined application and binary distributions are redistributed under the GNU General Public License v2.0 or later; see COPYING.
Original RDNA Cast additions are also offered under the MIT License by George Karagioules; see RDNA_CAST_ADDITIONS_LICENSE.md. That MIT grant applies only to original RDNA Cast additions and does not relicense OBS Studio or the combined OBS-derived application.
Bundled third-party libraries retain their own licenses. See THIRD_PARTY_LICENSES.md. Installers ship LICENSE.txt, COPYING, AUTHORS, and THIRD_PARTY_LICENSES.md alongside the application.