If your PC turns on and the fans spin up, but nothing is displayed on the screen, there's a problem that needs fixing. It might be one of the more common ones and be relatively easy to fix, or it may be more complicated. To figure out what's causing the issue and how to fix it, we're going to need to do some investigating.
We'll walk you through how to troubleshoot this issue and give you some great tools to try to fix it yourself.
Wait and reboot
Before you do anything, just wait a second. There's a chance that your PC is reconfiguring the memory or is taking an unusually long time to initialize your USB ports. Or it could be some other strange quirk of the boot process. If you're still staring at a blank screen after a couple of minutes, try rebooting the PC. It's surprising how many issues that can fix -- and booting up to a blank screen is one of them.
Check the monitor
It might seem simple, but just double-check that the monitor is turned on and is connected correctly to your PC. It should have some kind of LED indicator letting you know that it has power, and it should turn "on" even if it doesn't display anything. That may mean a logo bouncing around on the screen, or a message saying it's entering standby, or something similar.
The monitor also needs to be connected to the correct port on your PC. That's a video output from the graphics card, or, if you're using onboard graphics, the motherboard. If in doubt, unplug the cable from both ends and plug it back in again. If you have any reason to suspect the cable itself may be damaged, try replacing it with another one.
It's unlikely that the monitor is powered on but not functioning. However, you can also double-check it still works by plugging it into another device like a games console or another computer.
Check the post code
PC troubleshooting is a lot easier when the PC helps you figure out the problem, and fortunately, many modern PCs do. If your motherboard has an LED readout with a post code on it, a Q-Code display, or if it beeps at you in a specific pattern, note it down. Your motherboard manual or the manufacturer's website will have a glossary of what these codes mean and they'll lead you straight to the problem you're facing.
Once you know the problem, jump to the section below that's most relevant. If you don't have that code or your system isn't beeping or giving you any readout, continue with the steps below.
You can also buy post code test cards to plug into your PC to give you that functionality. We can't speak to how well they work, but they're an option if you want some extra help troubleshooting your issue.
Reset the CMOS
The CMOS is a tiny bit of memory that stores the basic BIOS/UEFI settings for your motherboard. Sometimes those settings can cause boot issues, so resetting that memory can get you back to the basics that worked just fine.
Your motherboard may have a CMOS/BIOS reset switch or jumper. Check your manual or manufacturer's website for more information. Otherwise, you can do it the old-school way by removing the small button battery on your motherboard. You may need to remove other components to get to it, but it's there. Pop it out, then remove the power cable from your PC and hold the power button down for 30 seconds. Then put the battery back in, and try turning your PC on again.
Remove everything unnecessary
Unplug everything from the back of the PC that you don't need, leaving only the keyboard, mouse and monitor plugged in, then try booting your PC again.
The next, more drastic step is to do the same with internal components. That means removing any add-in cards like USB hubs or network cards, any additional memory (you only need the one stick), any secondary storage drives that don't contain the operating system (you could remove them all if you want to be doubly sure, as you don't need a drive to get the PC to post and the monitor to turn on). You should also disconnect any cooling fans that aren't part of your CPU or GPU cooling and any fan controllers or RGB lighting systems.
If your PC supports onboard graphics, you could try removing the graphics card too, and trying with onboard graphics.
If your PC starts to work after removing everything, that's great news! Now, slowly reintroduce one component and peripheral at a time and reboot your PC to see if it stops working again. If so, you've found the problematic component.
Double-check the memory
Memory problems can cause PC post issues, so make sure the memory isn't causing problems by swapping it out for another kit if you have it. Alternatively, take all the sticks out bar one and try booting. If it doesn't work, swap that stick out for one of your other ones.
Consider your CPU
The CPU could be causing your problem. Take out all the memory and try booting the PC. It should show you a different error code or give you a series of post code beeps to tell you that there's no memory. If that happens, then the CPU should be fine. If it doesn't, you may have a CPU problem -- though it could also be the motherboard.
Reseating your CPU might fix the issue too. Follow our guide on installing a CPU for more help there.
Inspect for physical damage
At this point, it your PC still won't turn on, there's probably some damaged or incorrectly mounted hardware that's causing the problem. It might be worth having a look at your motherboard, graphics card, memory, and processor to see if there are any obvious physical signs of stress or damage.
If you find something that's obviously damaged, try replacing that component. Otherwise, the only real option you have is to test each component individually in a system that works, or opt for a new PC altogether.
Need a new processor? These are the best CPUs in 2024. Is the motherboard acting up? Here's how to choose a new one.
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