You power on your computer, the fans spin, the keyboard lights up — and the monitor just says “No Signal” and goes dark. Nothing you do seems to wake it. Before you assume your graphics card is dead, know this: in most cases, learning how to fix HDMI no signal on a PC comes down to a loose cable, the wrong input, or a port you didn’t know was disabled.
“No signal” is the monitor telling you it is powered on and working, but it is not receiving any video data through the HDMI cable. The cause sits somewhere between three suspects: the cable, the monitor’s input settings, or the PC’s video output. This guide walks through them in order, from the two-minute fixes to the deeper hardware checks, so you can find the fault without buying parts you don’t need.
Quick Answer
To fix HDMI no signal on a PC: unplug and firmly reseat the HDMI cable at both ends, make sure the monitor is set to the correct HDMI input, and plug the cable into the graphics card’s HDMI port (not the motherboard’s) if you have a dedicated GPU. Then press Windows + Ctrl + Shift + B to restart the graphics driver, and try a different HDMI cable or monitor to rule out hardware. If the PC worked before and stopped after an update, update or reinstall your GPU drivers in Safe Mode.
Start With the Five-Minute Hardware Check
Most “no signal” cases are solved here, so don’t skip these basics even if they feel obvious.
1. Reseat the cable at both ends
HDMI connectors can feel connected while barely making contact — especially if the cable hangs at an angle. Unplug the cable from both the PC and the monitor, then push each end firmly back in until it clicks or sits flush. Avoid sharp bends in the cable, which can crack the internal wires in cheap cables.
2. Confirm the monitor is on the right input
Monitors with multiple HDMI ports default to whichever they were last set to, and some switch inputs after a power cut. Press the input/source button on the monitor (or its on-screen menu) and select the exact HDMI port the cable is plugged into — HDMI 1 and HDMI 2 are different inputs, and “Auto” input selection is not always reliable.
3. Check the monitor’s power cable
It sounds silly, but a monitor whose screen shows the “No Signal” message is clearly powered. If the screen is completely black with no power LED, the issue is the monitor’s power supply, not HDMI. Plug the monitor directly into a wall socket instead of a multi-plug strip, which can under-power some screens.
4. Listen to what the PC is doing
If the PC’s fans ramp up normally and you hear a Windows login sound, the computer itself is fine — the problem is the video path. If the PC clicks off after a few seconds or beeps, note that down; it’s a boot failure, not an HDMI issue, and no cable swap will fix it.
Plug Into the Right Port: GPU vs Motherboard
This is the single most common cause on new builds and newly upgraded PCs. If your computer has a dedicated graphics card, the HDMI port on the motherboard (up high, near the USB ports) is usually disabled by the processor. The working HDMI port is the one on the graphics card itself, lower down on the case.
- No graphics card? Use the motherboard’s HDMI port — it’s the only one available.
- Graphics card installed? Plug the HDMI cable into the card’s port. The motherboard port will likely give you nothing.
- Recently added or moved a GPU? The cable may still be in the motherboard port from before the upgrade.
If you’re not sure which port is which, try both: shut the PC down, move the cable, and power back on. This test takes a minute and resolves a surprising number of “no signal” complaints. If you end up switching cables entirely, it’s worth knowing the practical differences between HDMI and DisplayPort before buying a replacement.
How to Fix HDMI No Signal on a PC With the Keyboard Shortcuts
If the hardware looks right but the screen stays dark, try the software resets before opening the case.
Restart the graphics driver
Press Windows + Ctrl + Shift + B at the same time. The screen will flash and Windows will reload the graphics driver — Microsoft documents this as the standard way to recover a blank or unresponsive display. It works even when the screen is showing “no signal,” because Windows may be sending video to a display output it hasn’t detected properly.
Cycle the display mode
Press Windows + P and then the arrow keys and Enter to switch between “PC screen only,” “Duplicate,” and “Extend.” On multi-monitor setups, the PC sometimes wakes with the wrong output active, especially after sleep. If you’re using a TV, the same problem can show up as the image landing on the wrong device — the troubleshooting steps in our guide on monitor no signal while the PC is running cover this scenario in more detail.
Force the monitor to wake
Some monitors don’t wake from sleep when the PC does. Turn the monitor off with its power button (not by unplugging it), wait 30 seconds, then turn it back on. Unplugging and replugging the HDMI cable while the PC is on can also force a fresh handshake between the devices.
Update, Reinstall, or Roll Back Your GPU Driver
Driver problems are the leading cause of “no signal” that appears suddenly — after a Windows update, a new game install, or out of nowhere on a machine that worked yesterday.
If you can see the screen at all
Open Device Manager (right-click the Start button), expand “Display adapters,” right-click your GPU, and choose “Update driver.” If the problem started right after a driver update, go to Properties → Driver and use “Roll Back Driver” instead. For NVIDIA cards, grabbing the latest release directly from the official NVIDIA driver downloads page is more reliable than Windows Update, and choosing the “clean installation” option during setup clears out conflicting old files.
If the screen never shows anything
You can’t update a driver you can’t see, so you need another way in:
- Boot into Safe Mode. Windows uses a basic display driver in Safe Mode, which often works even when the normal driver is broken. Force it by turning the PC on, holding the power button to shut it down as Windows starts, and repeating until you see the recovery menu → Troubleshoot → Advanced options → Startup Settings → Restart, then press 4 for Safe Mode.
- Uninstall the broken driver. In Safe Mode, open Device Manager, uninstall the display adapter (tick “delete the driver software” if offered), and restart. Windows will fall back to its basic driver and usually restore the picture.
- Reinstall fresh. Once you can see the screen, install the latest driver from the GPU manufacturer’s site.
A word of caution: only download drivers from the GPU maker’s official site or Windows Update. Random driver-updater tools and unofficial download sites are a common way to end up with malware, and they won’t solve a hardware-level fault anyway.
Resolution and Refresh Rate Mismatches
A PC sending a resolution or refresh rate the monitor doesn’t support produces the same “no signal” message as a dead cable. This often happens after switching monitors — the PC remembers the old screen’s settings.
- Boot into Safe Mode (which runs at a low, universally supported resolution) and set the display to 1920×1080 at 60 Hz, then restart normally and raise it step by step.
- In the monitor’s menu, disable any “overdrive” or overclocked refresh-rate modes while testing.
- If you recently raised the refresh rate, our guide to enabling the correct monitor refresh rate explains how to set it back safely.
Isolate the Fault: Cable, Monitor, or PC
If everything above checks out, it’s time to figure out which device is broken. Swap one thing at a time:
| Test | What it tells you |
|---|---|
| Try a different HDMI cable | If the picture appears, the old cable was faulty. Cheap cables fail more often than people expect. |
| Try a different port on the monitor | If HDMI 2 works but HDMI 1 doesn’t, the monitor’s port is the problem. |
| Connect the monitor to another PC or laptop | If it works there, your monitor is fine and the fault is in the PC. |
| Connect the PC to a TV | If the TV shows a picture, the PC is fine and your monitor needs repair. |
| Try a DisplayPort cable instead | If DisplayPort works but HDMI doesn’t, the GPU’s HDMI port may be damaged. The DisplayPort troubleshooting steps in our DisplayPort no signal guide overlap here. |
Work through these in order. Once one test gives you a picture, you’ve found your culprit — don’t keep swapping.
Deeper Hardware Checks (Only If Software Fixes Failed)
If a known-good cable, a known-good monitor, and a clean driver all give you “no signal,” the fault is inside the PC.
Reseat the graphics card and RAM
Power off, unplug the PC, and open the case. Push the graphics card firmly into its slot (the latch should click), and make sure its power connectors from the power supply are fully seated — most cards won’t output video without them. While you’re in there, reseat the RAM sticks too; a loose stick can prevent the PC from booting far enough to send any video signal.
Reset the BIOS
A wrong BIOS setting — particularly after enabling features like Secure Boot or changing the primary display adapter — can kill the HDMI output. Clear the CMOS (remove the motherboard’s coin-cell battery for a minute with the PC unplugged, or use the clear-CMOS jumper) to restore defaults.
Consider a failing GPU or power supply
If the card’s fans spin at full speed with no picture, or the PC only boots with the GPU removed, the card itself may have failed. A dying power supply can produce the same symptom by failing to deliver stable power to the GPU. At this point, testing with a borrowed GPU or taking the machine to a repair shop is the sensible move — there’s no software fix for dead hardware.
Frequently Asked Questions (FAQs)
Why does my HDMI say no signal when the PC is on?
The monitor is powered but receiving no video data. The most common reasons are a loose or faulty cable, the monitor set to the wrong input, the cable plugged into a disabled motherboard port, or a crashed graphics driver. Work through the hardware checks first, then try Windows + Ctrl + Shift + B.
Can a bad HDMI cable cause no signal?
Yes — it’s one of the top causes. HDMI cables fail silently from bent connectors, stretched wires, or poor quality. Swapping in another cable is the fastest way to rule it out. If you’re buying a replacement, a mid-priced certified cable is fine; you don’t need expensive “premium” branding for typical setups.
How do I fix HDMI no signal after a Windows update?
Windows updates sometimes replace your GPU driver with a version that doesn’t work properly. Boot into Safe Mode, open Device Manager, and roll back or uninstall the display driver, then install the latest driver from your GPU manufacturer’s official site. Microsoft’s own guide to troubleshooting blank screens in Windows walks through the Safe Mode and driver recovery steps in detail.
Why does my monitor work with my laptop but not my PC?
That test result points squarely at the PC. The most likely causes are the cable plugged into the wrong port (motherboard instead of GPU), a driver issue, or a resolution the monitor can’t handle. The monitor itself is fine — focus your troubleshooting on the PC side.
Should I buy a new cable or a new monitor first?
Always test the cable first — it’s cheap and the most likely failure point. Borrow another cable before buying anything. Only suspect the monitor after you’ve confirmed the PC works with a different screen and a different cable.
The Bottom Line
HDMI no signal on a PC almost always comes down to something simple: reseat the cable, confirm the right input, and make sure you’re plugged into the graphics card, not the motherboard. If those don’t do it, the Windows + Ctrl + Shift + B driver reset and a clean driver reinstall solve the software side, and a one-at-a-time swap of cable, monitor, and PC pinpoints the hardware. Work through the steps in order and you’ll find the fault — usually without spending anything.
Last Updated: 8 October 2026
About the author: Zaviyar Sultan is a UAE-focused writer at Paxi, covering driving, visas, banking, insurance and everyday UAE life. His guides are researched from official UAE government and regulator sources and updated regularly.
Paxi is an independent informational website, not affiliated with the UAE government or any agency mentioned; content is general information only, not legal, immigration or financial advice; verify critical details with official sources before acting.