How to Start OBS Replay Buffer Automatically on Windows 10 and 11

The idea: an always-on replay buffer​

Sherback says OBS's Replay Buffer does the same basic job as ShadowPlay's Instant Replay. It keeps a rolling window of recent footage and writes it to disk when you press a hotkey. OBS's overview guide documents the same workflow: you enable the Replay Buffer in the Output settings. You then set the hotkey that saves it under Hotkeys.

The catch has always been remembering to start it. Two launch parameters remove that step.

Step by step: the one-click setup (Windows)​

OBS's launch-parameter documentation confirms the flags and the shortcut method. The Startup folder step comes from Sherback's article.

1. Build the scene first. The flags don't configure anything else. You still need a working scene with the right capture source. OBS lists Display Capture for a whole display on Windows and Linux. It lists Game Capture as a Windows-only, high-performance source for 3D games.
2. Enable the Replay Buffer and set a duration. Open Settings, then Output, and enable it. Then assign a save hotkey under Hotkeys. Sherback uses F10. If you want ShadowPlay's usual Alt+F10, he says to turn off Instant Replay in the NVIDIA App so two buffers aren't running at once.
3. Copy your OBS shortcut and open its Properties. Add the parameters after the path to obs64.exe in the Target field, outside the closing quotation mark. OBS documents this procedure.
4. Append the flags. --startreplaybuffer starts the Replay Buffer automatically. --minimize-to-tray starts OBS minimized to the system tray. OBS's overview guide notes that the system tray icon must be enabled in General settings for hiding to tray to work. If you use several profiles or scene collections, add --profile "name" and --collection "name". Sherback says this prevents recording a black screen from the wrong scene.
5. Add it to startup. Press Win+R, type shell:startup, and put the shortcut in the folder that opens. Sherback reports that OBS then launches at login and starts buffering before any game is open.
6. Test it. OBS's quick-start guide strongly encourages a test run rather than assuming the first configuration is right. Save a real clip and check the video and every audio track.

A note on automation. OBS warns that if you launch it from scheduled tasks or similar means, you should also set the "Start in…" working directory to the folder containing obs64.exe. A Startup-folder shortcut with a proper Target usually avoids this, but the warning matters if you move to Task Scheduler.

Where OBS goes beyond ShadowPlay​

These are Sherback's comparisons. They are his assessment, not benchmarks.

• Audio. He says OBS can use up to six audio tracks and isolate individual apps with Application Audio Capture. OBS's guide confirms per-application sources exist from OBS Studio 28 on Windows 10 version 2004 or later and Windows 11. The guide's own caveats are useful:
  • If you use these sources, disable the global Desktop Audio source to avoid echo.
  • Some apps output audio in ways that don't work with the capture method, and OBS describes a virtual audio cable workaround for them.
  • The guide describes this as a Windows feature, so don't assume it behaves the same on Linux.
• Encoder control. On his RTX 5080, he says OBS uses the same NVENC encoder as ShadowPlay, but he chooses codec, rate control and bitrate himself. OBS's hardware-encoding page says NVENC works on Windows and Linux, needs a GeForce 750 Ti or newer, and works best on Turing-generation hardware or later. It also says to keep GPU drivers current. The RTX 5080 is his example, not a requirement.
• Memory versus storage. Sherback says OBS holds the buffer in RAM, while ShadowPlay writes a temporary file. In his view that spares your SSD constant writes, but long, high-bitrate buffers can strain a system with little memory. I couldn't verify the RAM-versus-temp-file detail against NVIDIA documentation. Treat it as his account, and size your buffer to your hardware.

Fixing the display-sleep problem​

Sherback warns that a running Replay Buffer keeps the display awake. His fix is powercfg /requestsoverride process obs64.exe display in an elevated terminal. Microsoft's documentation supports the mechanism. powercfg /requests enumerates application and driver power requests, which prevent the computer from automatically powering off the display or sleeping. /requestsoverride sets an override for a particular process, service, or driver. The request types are Display, System and Awaymode.

A cautious approach:

1. Run powercfg /requests in an elevated terminal and confirm obs64.exe appears under DISPLAY.
2. Apply the override using the name shown there.
3. Check the result. One Microsoft Q&A user reported that an override didn't resolve their problem. Overrides aren't guaranteed to fix every sleep issue.
4. To undo it, run powercfg /requestsoverride with the caller type and name but omit the request parameter, according to a Microsoft Q&A answer.

The Linux version​

Sherback says the same approach works on Linux, where the NVIDIA App isn't available. He describes adding a .desktop file in ~/.config/autostart with the Exec line obs --startreplaybuffer --minimize-to-tray. OBS's launch-parameter page documents only Windows and macOS setup, so that file location is his instruction rather than official guidance. Packaging and executable names can vary by distribution and install method.

OBS's 30.2 release notes, dated July 12, 2024, confirm that the native NVENC encoder gained Linux support, including NVENC AV1. They also added Linux shared-texture support for NVENC, QuickSync and VA-API. Sherback says AMD cards encode through VA-API. Check your own GPU, driver and codec combination before assuming parity with Windows.

Is it worth it?​

Sherback is fair to ShadowPlay. He says it installs with the driver, detects games automatically, and sorts clips into per-game folders with no configuration. He says OBS needs an afternoon of setup, and that most people would rather spend that afternoon playing. His verdict is that OBS suits people who edit clips, talk over gameplay, record their desktop for work, or split time between Windows and Linux. If you only save and share clips, he says ShadowPlay is fine.

My take, from general industry knowledge, is that the choice comes down to how much you want to configure. One caveat on the title: "one click" is really "configure once, then forget." The flags only start the buffer. You still own the scene, the sources, the hotkey, the buffer length, the encoder settings and the folder where clips land. That is the afternoon Sherback mentions.

Quick checklist​

• Confirm the correct capture source (Game Capture for games, Display Capture for the desktop).
• Enable the Replay Buffer, set its length, and assign a save hotkey.
• Disable ShadowPlay Instant Replay if you reuse its hotkey.
• Append --startreplaybuffer and --minimize-to-tray, plus --profile and --collection if needed.
• Place the shortcut in shell:startup.
• Save a test clip and check both video and audio.
• If the display won't sleep, inspect powercfg /requests before applying an override.