MonitorNap

Intelligent, lightweight multi-monitor power management utility for Windows using VESA DDC/CI hardware control.

MonitorNap is an intelligent, lightweight Windows utility that automates secondary monitor power management based on mouse cursor position. Utilizing direct VESA DDC/CI hardware control via DisplayPort, HDMI, or DVI, it automatically puts secondary displays into low-power standby when the cursor leaves the screen, and instantly wakes them up the moment the cursor re-enters.

Unlike native Windows display settings which force desktop reconfiguration and rearrange open windows when a monitor is disabled, MonitorNap keeps Windows believing the display is active while commanding the physical panel hardware to enter low-power standby or dim.

• Cursor-Based Auto Standby & Wake: Automatically places the secondary monitor into low-power standby when the mouse cursor is not present on or moves away from that display, and instantly restores power and original brightness as soon as the cursor re-enters the monitor's screen bounds.
• Direct Hardware Control: Interacts with display microcontrollers via native Win32 and DXVA2 APIs (dxva2.dll) without third-party drivers or runtime dependencies.
• Configurable Standby Modes:
  • Dim then Sleep (Default): Reduces panel luminance to 0% as a visual warning 60 seconds before putting the panel into standby.
  • Dim Only: Drops hardware brightness to minimum without sending full standby commands.
  • Black Curtain: Displays a non-activating, borderless black overlay for displays or adapters lacking DDC/CI standby support.
• Customizable Global Hotkey: Toggle secondary monitor states instantly using configurable system-wide key combinations (Ctrl, Alt, Shift + Key).
• Smart Standby Suppression:
  • Fullscreen Detection: Automatically blocks standby if games, media players, or presentations are running fullscreen on the target display.
  • Window Title Filtering: User-configurable keywords (e.g., YouTube, VLC, PotPlayer) to inhibit standby during windowed media playback.
• Per-Monitor Targeting: Select specific secondary screens to manage in multi-display setups.
• Minimal Footprint: Native C# implementation consuming ~3-4 MB of RAM.

• OS: Windows 10 or Windows 11 (64-bit).
• Display: Monitor with DDC/CI support enabled in its OSD settings (enabled by default on most modern displays).
• Connection: Standard DisplayPort, HDMI, USB-C, or DVI cable.

winget install EhsanCh.MonitorNap

Download the latest standalone executable from the Releases page. MonitorNap is portable and requires no installation.

The project can be compiled directly using the standard C# compiler (csc.exe) bundled with the .NET Framework on Windows.

1. Clone this repository:

   git clone https://github.com/EhsanCh/MonitorNap.git
   cd MonitorNap

2. Build using the provided script:

   build.bat

   Alternatively, invoke csc.exe manually:

   C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe /target:winexe /optimize+ /win32icon:"assets\app.ico" /out:"dist\MonitorNap.exe" src\*.cs

3. The compiled binary will be placed in dist\MonitorNap.exe.

Contributions, issue reports, and pull requests are welcome. Feel free to review the repository issues or submit enhancements.

Ehsan Chavoshi (@EhsanCh)

This project is licensed under the MIT License.