How to fix a PC that turns on but displays nothing on the monitor: Six common fixes to try

There's no way to tell exactly what causes the CPU to turn on but not display anything on the monitor, but you can try a few common fixes to get it up and running properly again.

Check your monitor

Look for loose connections

Before we dive into more complex troubleshooting methods, I suggest you ensure the monitor is connected and working properly. The solution to this particular problem could sometimes be as simple as disconnecting all the cables and putting them in place again. It may even be worth turning the monitor on just by itself before connecting it to the computer to see if it powers up and shows its boot animation or diagnostic information to ensure nothing is wrong with it. Below are a few things you can do to test a monitor that isn't working:

• Check for disconnected power and data cables.
• If you use a multi-monitor setup, ensure all monitors are connected properly. It may even be worth trying the connection with a single monitor before connecting the rest.
• Test your PC with a different display unit to see if it's working properly. This will allow you to narrow down the root cause.

Wait for the PC to boot properly

Things like 'memory training' could lead to slow POST times

While highly unlikely to be the reason, don't eliminate slow booting times because you're not seeing a display output. Your PC may be indeed booting or is trying to boot, and you're just not giving it enough time. There are plenty of reasons for a PC to boot slowly, with things like memory training being a few main culprits.

I personally experience this a lot as my T-Force DDR5 memory kits on an AM5 platform often take ages for memory training before I see an output signal on the monitor. It's easier to identify these errors if you have a motherboard with a Q-code display that tells you exactly what the error is. In such a case, you can wait it out and let the PC completely boot properly.

Try performing a hard reset

A simple reset is all you need sometimes

Before we get into the PC case and start taking apart different components, I recommend performing a hard reset to see if it fixes the issue. Remember that this differs from performing a factory reset, as we're not wiping the operating system. The objective is to drain the residual power from the board's capacitors, which may keep your system from booting properly. To do this:

1. Turn off your PC, and disconnect the power cable.
2. Disconnect/remove all the external devices like thumbdrives, memory cards, and more.
3. Press and hold the power button for 10 to 15 seconds to drain any residual power.
4. Connect all the power cables and external devices you previously removed, and try rebooting the PC.

Reset BIOS settings

Reseat the CMOS battery

Your computer's Basic Input/Output System (BIOS) could also be responsible for causing boot-up issues, preventing the monitor from receiving the output signal. It may be worth resetting it to restore the settings to the last saved configuration. You will, however, have to reset the BIOS to its factory settings by reseating the CMOS battery since you can't access the BIOS interface without the display signal. To remove the battery:

1. Shut down your system and unplug the power adapter.
2. Press and hold the power button for 10–15 seconds to drain any remaining charge from the motherboard's capacitors.
3. Remove the side panel of your PC case to reveal the motherboard and locate the CMOS battery, which can be found around the PCI-e slots (ATX and Micro ATX motherboards) or near the IO ports (Mini-ITX motherboards).
4. Press down on the latch on the CMOS battery to remove it.
5. Either replace it with a new battery (optional) or install the same one by placing it in the battery slot with its positive side up and pushing it down.

Reseat the components

A simple and effective method

Reseating some components of your PC that are relatively easy to take apart is also a good way to troubleshoot for this particular. Don't underestimate the power of uninstalling and reinstalling the components, as it will help you fix loose connections if there are any. Some components like the GPU, RAM sticks, or even CPU coolers can sometimes pop out of place, causing trouble. You don't necessarily have to worry about components like the CPU coming loose, so consider reseating them only if you think it is absolutely necessary. While you are at it, I suggest checking all the power connections on the motherboard, too, as these cables and connectors often lose connections very easily.

Don't ignore the PSU

Power supply units often cause the most trouble

It's easy to ignore the power supply unit and take it out of the equation when you see the CPU turning on, along with the lights and fans inside the case. Those components often require much less power to start up, and your PSU may be unable to supply enough power for the rest of the core components, like the processor and graphics card. The PSU is one of those components that cause most problems on a computer, so I recommend testing it manually with a multimeter or with the help of a power supply tester.

Finding the quick fix

Those are some common fixes you can try if you are stuck with a PC that turns on but displays nothing. If none of the above methods work and you're still having issues, then you can even try connecting your PC to a different monitor or vice versa to see if you can narrow the issue down to either the PC or the monitor. Alternatively, you can even look for things like electrical shorts that may have permanently damaged some connections. Remember that there's only so much you can do in the name of troubleshooting to get your PC up and running. If you are dealing with a particularly old PC or a monitor that refuses to power on or work properly, it may be time to replace it with one of the best monitors or gaming PCs.