How to enable DDC/CI on your monitor

DDC/CI must be enabled in your monitor’s on-screen menu (OSD) for hardware brightness control. Here’s what to look for and common names.

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Most monitors ship with DDC/CI enabled, but some models have it off by default — or it gets turned off after a factory reset.

DDC/CI is usually a toggle inside the monitor’s on‑screen display (OSD).

Where to find it

  • Look in OSD menus like: Settings, System, Other, or General.
  • Common names: “DDC/CI”, “DDC”, “Monitor Control”, “External Control”, or “PC Control”.
  • Enable it, then power-cycle the monitor (off/on) if your app still can’t detect it.

If it’s enabled but still flaky

  • Try a direct cable (DP/HDMI) instead of a dock/adapter to rule out DDC pass‑through issues.
  • Some monitors respond better after opening the OSD menu once (it can “wake” the control channel).
  • If your chain blocks DDC, use GPU dimming for that display.

Related guides

Frequently asked questions

What does DDC/CI stand for?

DDC/CI is a monitor control channel that lets a PC send commands like brightness to a monitor, similar to the on-screen display controls.

Where is the DDC/CI toggle usually located?

Commonly under Settings, System, Others, or Input in the monitor’s OSD. It may be called DDC/CI, Monitor Control, or External Control.

Do all monitors support DDC/CI brightness?

No. Many do, but some expose limited controls or behave inconsistently depending on the input and cable/adapter chain.