How to Fix HDMI No Signal on Windows 11

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My Technician
Windows 11DisplayHardwareFix

The Problem

The monitor powers on but shows No signal, HDMI no signal, or a blank screen—even though Windows sounds like it is running (fans spinning, keyboard Caps Lock works). This is different from Windows not detecting a second display at all; here the panel never gets a picture on HDMI.

Monitor not listed in Settings at all? See second monitor not detected for Extend/Detect and ghost-display fixes.

Symptoms

  • HDMI monitor worked yesterday; after sleep or reboot it stays on No signal.
  • Laptop lid closed + external HDMI never wakes the panel.
  • TV shows signal on another device (game console) but not from the PC on the same port.

The Fix: Step-by-Step

Step 1: Power-Cycle Monitor and PC

  1. Turn off the monitor, unplug HDMI from both ends for 30 seconds, plug back firmly.
  2. Shut down the PC (hold power 10 seconds if needed), not just sleep.
  3. Boot with only one display connected first, then add the second after Windows loads.

Step 2: Correct Input and Cable

  1. On the monitor OSD, select HDMI 1 vs HDMI 2—many panels have multiple ports.
  2. Try another HDMI cable or a DisplayPort cable if the GPU has DP (HDMI adapters on cheap dongles often fail at 1440p/4K).
  3. On desktops, plug into the graphics card rear ports, not the motherboard HDMI (unless you use CPU graphics only).

Step 3: Force Display Output

  1. Press Win + P → choose PC screen only, wait 5 seconds, then Extend or Second screen only.
  2. Settings → System → Display → Detect → Identify to confirm Windows sees the panel.
  3. Still black? Ctrl + Alt + Del → click the power icon → Restart (sometimes wakes the GPU after a bad sleep).

Step 4: Update or Roll Back the GPU Driver

  1. Boot if you can, or use Safe Mode if the screen stays black after login.
  2. Device Manager → Display adapters → right-click your GPU → Update driver (or download from NVIDIA, AMD, or Intel).
  3. Problem started right after an update? Properties → Driver → Roll Back Driver.

Step 5: Reset Display Settings and Resolution

  1. Settings → System → Display → set Scale to 100% temporarily.
  2. Under the external monitor, pick a safe resolution (1920×1080) and 60 Hz refresh.
  3. Remove custom color profiles: Settings → System → Display → Color profile → try the default monitor profile.

Step 6: BIOS and Hardware Checks

  1. If no display from power-on (no BIOS logo), see black screen on boot and PC won't turn on.
  2. Test the PC on another monitor or TV to rule out a failed panel input.
  3. Reseat the GPU (desktop) or try USB-C/DP on a laptop dock—bad docks often show No signal while charging still works.

When HDMI Is Fine but Colors Look Wrong

If you get a picture but HDR looks gray or blown out, switch to fix HDR washed-out colors. Flickering after signal returns is covered in screen flickering fixes.