Black screen and no HDMI signal? A checklist before the lab

Five checks before you open the case

1. Make sure the monitor is on the right input. HDMI1, HDMI2 and DisplayPort are different inputs. On a console or laptop, use the video port, not a charge port that looks similar. Try the same cable on a TV: if you get a picture there, the monitor or that input is the problem.

2. Swap the cable and the input. Don’t bend it until it “catches”. A cheap HDMI cable fails on one pin and gives a black screen on and off. If the card or laptop has a second output, try it. Don’t stack adapter on adapter.

3. Tell a live PC from a silent one. Fans spinning and a drive light blinking with no picture is usually the video path. Total silence: check power first, as in the “PC won’t turn on” guide. Don’t mix the two cases.

4. On a PC with a separate graphics card, the cable belongs in the card, not the motherboard, when the system is set up that way. Reseat the card at home only if you already open cases calmly: unplug the wall, touch the case metal, press the card until the latch clicks. Don’t flex the board.

5. Safe Mode or another screen separates a driver fault from hardware. Picture on the TV but not on your monitor - the monitor. No picture anywhere, even with another cable - bring the PC, console or monitor in. Don’t replace a graphics card on a guess.