Can BetterDisplay create an EDID for a custom display timing?

BetterDisplay can import a prepared EDID binary and apply it on supported connections, but its loader does not edit individual timing fields. Create or edit the binary in an EDID editor, using timing information that the display or video processor actually supports.

On Apple silicon, open Settings > Displays > [display] > Display EDID > Load Custom EDID…, then Load EDID Data…. Inspect the interpreted data and any warnings. Loading the file saves it in BetterDisplay. It does not apply the override immediately.

With Pro and a supported connected external display, choose Apply Custom EDID Now and confirm Apply EDID. This changes the EDID macOS uses without writing the display's permanent memory. The connection must have an accessible framebuffer service. Loading a binary cannot create a usable connection to a device macOS cannot detect.

An advertised timing is not proof that the entire signal path can carry it or that the receiving hardware accepts it. In particular, a custom ultrawide timing does not guarantee that two video processors can run together at that size and refresh rate. Check the processor's supported timings and the Mac's output capabilities before relying on the configuration.

Applying an override can interrupt the picture or change the display identity. To remove it, use Reset Factory EDID (Unapply). If automatic application is enabled, disable that first. If the picture becomes unusable, physically reconnect the display. Hold Shift while starting BetterDisplay to avoid automatic application in safe mode.

Loading EDIDs for several outputs is not a general-purpose way to combine them into one frame-locked tiled display. The Mac, adapters and receiving hardware must support the intended topology. A custom mode appearing in the list does not prove that the outputs are synchronized, and virtual-screen mirroring does not establish that either. Verify the complete signal path before relying on it for an LED wall.

Write EDID to Device is a separate operation that modifies device memory and is not required for this software override. See Display EDID for the complete workflow, recovery behavior and the separate Intel system-configuration path.