Monitor No Signal: The Complete Fix

Published 2026 · 3 min read

"No signal" is usually a cable, the wrong input, or a graphics driver — in that order.

1. The cable

Make sure the display cable is fully inserted on both ends. Try a different cable (HDMI vs DisplayPort) and a different port. On desktops, use the graphics card ports, not the motherboard's.

2. The input source

Monitors with multiple inputs need the right one selected. Press the monitor's input button and cycle through HDMI 1, HDMI 2, DisplayPort, etc.

3. A black screen with the PC running

Try waking it, then restart the PC. If it recurs, the graphics driver is likely stuck — update or reinstall it. Test the monitor on another computer to rule out the panel.

Interactive version

Use the no signal fixer — tell it what the monitor shows and get the exact steps.

How "no signal" is diagnosed

"No signal" means the monitor is on but receiving nothing from the PC. Work from the cheapest check to the hardest: the input source, the cable, the port, then the graphics driver and hardware. Nine times out of ten it is the first two.

Input source mistakes

Monitors with HDMI and DisplayPort inputs often sit on the wrong one. Use the monitor's menu button to cycle inputs rather than assuming the port you plugged into is selected. Also try the graphics card's other ports - one HDMI or DP port on a card can fail while the others work.

Why safe mode is a useful test

If the screen shows only in Windows Safe Mode or at a lower resolution, the graphics driver or refresh rate is the culprit - reinstall the driver or lower the refresh rate. If there is no picture even in the BIOS/boot screen, the problem is the cable, port, monitor or GPU, not Windows.

Quick hardware checks

Reseat the cable at both ends, test with a different cable, then plug the PC into a TV to prove whether the monitor or the PC is at fault.