PC Tower Not Connecting To Monitor?
You’ve just assembled your brand-new PC and connected it to your monitor, only to be disappointed by a no-signal display. Or perhaps your PC display was working fine the other day but is suddenly giving you problems. Here’s what to do when your PC tower doesn’t want to connect to a monitor.
While a no-connectivity issue is quite frustrating, you’ll be able to deal with it at home most of the time.
Important tip: I strongly recommend removing any extra display cables to multiple monitors to ensure that you don’t have other factors causing your monitor to stay blank before you continue your troubleshooting.
Reasons And Fixes For A Monitor Not Connecting To A PC
Keep reading for a step-by-step troubleshooting guide on restoring connectivity between your PC and monitor.
1. Either Your Monitor or PC Is Turned Off
We must get the seemingly obvious out of the way before moving on to the more problematic causes of a no-signal display.
We don’t want to spend a long time mistakenly fixing a loose connection or a faulty component and then have the actual issue turn out to be a simple one-click fix.
And, to be honest, you’d be surprised at how often we miss the things that are in plain sight.
Your monitor and PC must be on and receiving power to generate a display.
You can confirm that both units are on by inspecting the tiny LED lights they typically have.
If you have an older PC case that doesn’t give you any visual feedback when turned on, you may have to check for other signs of activity, such as spinning fans or a rotating hard disc.
How to Fix
Check that your monitor and PC are connected firmly to their respective power adapters and turned on. If this was all it took to bring back your display, congratulations.
If not, don’t worry. Keep reading as we go through the most common causes.
2. Your Monitor Is Set To Display the Wrong Input Source
Modern-day monitors come equipped with several ports. You could connect a suitable cable to any of these ports, and your monitor will detect the incoming signals and display them automatically.
However, it is possible to manually alter a monitor’s settings to use signals from a particular input source.
This can usually be done using the tiny control buttons on the monitor’s frame.
For example, you may have mistakenly set your monitor to inputs received via HDMI when the monitor and PC are connected via a Display Port.
In this case, your monitor will show you a no-signal alert until you instruct it to display HDMI.
If you’re struggling to understand, it can help to think of a TV broadcast being played on channel 1 while your TV is set to display a dead channel 2.
How to Fix
Before anything else, try simply reconnecting your display cable. Monitors can detect incoming signals and usually revert to the appropriate channel automatically.
If this doesn’t happen, chances are your video data cable is faulty (we’ll cover how to deal with that in the next section).
For now, it’s worth trying to manually change the input source setting on your monitor.
How exactly you change the input display setting differs from monitor to monitor, but it’s typically done via the control buttons built into the monitor’s frame.
They’re conventionally located alongside the power button.
You may have to fiddle around with these control buttons for a bit to learn what they’re for if you’ve never used them before.
You can also consult your monitor’s user manual to learn how to change the input source.
You can look up your monitor’s model online if you don’t have the user manual.
3. Your Display Cable Is Connected To Your Motherboard Instead of Your Graphics Card
The display cable carries signals from your computer to your monitor. It’s supposed to be connected to your GPU on one end and your monitor on the other.
Many motherboards have HDMI and similar ports built onto them. You may have mistakenly plugged your video cable into one of the ports on your motherboard instead of your graphics card.
To understand why this leads to a no-signal alert, I must first explain how a computer generates your monitor’s display.
The GPU, the Graphics Processing Unit, generates this display data, so one end of your cable is usually plugged into it.
But if that’s the case, why do motherboards have ports to begin with? Let me explain.
Many CPUs (Central Processing Units) have an integrated graphics processing unit built into them.
This means a computer can have two GPUs at the same time. As you might have guessed, integrated graphics are far weaker.
The ports on the motherboard connect to this integrated unit on the CPU. If your primary GPU fails, you’ll have a backup option.
The thing is, many CPUs these days don’t have an integrated graphics unit. These motherboard display ports connect to a dead end.
Yet another element comes into play here: the graphics accelerator.
Some older motherboards used to have these units built-in, and they could generate display even when paired with a CPU without integrated graphics. Today, virtually no motherboards have it.
Connecting your video cable to your motherboard won’t give you anything if your CPU lacks integrated graphics.
How to Fix
Check whether your display cable is connected to one of your GPU’s ports or one of your motherboard’s ports.
If it’s the latter, plug it out and connect it to your GPU. If you weren’t getting a display due to the lack of integrated graphics, doing this should bring it back.
4. There’s a Fault in the Display Cable
A loose cable is the most common culprit behind a no-signal display. Your monitor probably only connects to 2 cables: one for power and one for the monitor.
In modern setups, the video cable will be an HDMI or Display Port cable. DVI and VGA cables are still used but are much less common.
Note that HDMI and Display Port cables pretty much look the same. It’s just that they connect to different ports.
When diagnosing and fixing a no-signal alert on your monitor, it matters little exactly which type of cable you’re using. If it’s not connected properly, your PC and monitor won’t be able to communicate.
A faulty or damaged display cable will result in the same problem.
Also, remember that if you’re using an adapter (such as an HDMI to Display Port adapter) to deal with compatibility issues, the fault may lie within the adapter itself.
How to Fix
- Identify your system’s display cable and disconnect it from both ends.
- Examine the condition of both of the cable’s connectors. Look for physical damage or discoloration.
- Examine the ports these connectors plug into. Clear out the dust inside these ports using a cotton swab or compressed air. Do this while the PC is off.
- Examine the physical integrity of the cable itself. Sometimes, rats and similar rodents will chew on cables, but this is unlikely to have happened unless the system remained in storage for a while.
- Plug the cable back in and check for a display.
You might have a faulty cable if nothing pops up on the screen. Try connecting your PC and monitor via another cable to find out.
If a second cable works, you can confidently conclude that a faulty cable was causing the no-signal display.
If there’s still nothing on the screen, you’ll have to move on to the next step.
5. One of Your PC Components Is Loosely Connected
Your computer comprises multiple components that operate in tandem to maintain the system’s normal function and generate a display on your screen.
Even if one of these components loses its connection to the rest, the system can cease functioning. In such a case, one of the consequences may be a no-signal situation.
The next step is ensuring all PC components are connected firmly to their respective sockets/ports and working normally.
This includes the RAM, CPU, GPU, storage drives, PSU, and motherboard.
How to Fix
We’ll start by checking the integrity of the external cables. We’ve already examined the display cable, but feel free to give it a second checkup.
Ensure the following two cables are connected to the electrical outlet and their respective ports.
- Check your monitor’s power adapter.
- Check your PSU’s power cable.
You’ll have to open your PC using a screwdriver for the next step. Turn off your PC before you continue.
- Check your RAM sticks. A computer won’t start if the RAM isn’t connected properly, which may be causing the black screen. RAM sticks make a clicking noise when they’re pushed into place.
- Check your storage device. Whether it’s a hard drive, an SSD, or an NVME drive, your computer needs it to work to boot. Without a functional storage device, your computer may fail to boot, take you to the BIOS menu, or end up on a black/blue screen identical to a no-signal situation.
- Make sure your GPU is connected to your motherboard and its dedicated power connector if it needs one. The GPU produces a display on your monitor’s screen, so it should work properly.
- Ensure the internal components of your PC are connected to the power supply, except those that draw power via the motherboard—RAM sticks, for example.
6. Your Graphics Card Isn’t Producing a Display
If you’ve tried all the above and the display still isn’t working, the problem may lie in your graphics card, your discrete GPU, to be more precise.
As mentioned, the graphics card produces the display you see on your monitor.
Unfortunately, a GPU can give out due to many reasons.
They naturally have a shorter lifespan than many other components in a computer because they consume a lot of power and run very hot.
This is also why your GPU likely has more fans than anything else on your PC.
On average, GPUs last 5 to 10 years. This value will be closer to most people’s lower end of the stated range.
GPUs can also fail due to overheating. This usually happens when their thermal solution (the attached fans) fails to keep up with the chip’s requirements for heat dissipation. Running hot reduces lifespan considerably.
Sometimes, GPUs will short-circuit. Ultimately, these chips are precisely crafted pieces of electronic hardware, so this is to be expected.
A GPU is at increased risk of short-circuiting if a faulty power supply powers it.
How to Fix
A professional must check out a faulty GPU to ensure it’s not working.
It cannot be easily done at home without the right equipment and expertise or spare parts.
Still, there are a few things you can try to test if your graphics card may be working:
- Disconnect the GPU from the motherboard. Inspect it for signs of damage, typically declaration and burns. Clean the PCI connectors that plug into the motherboard.
- Reconnect the GPU to its PCI slot firmly.
- Ensure the GPU is connected to its dedicated power connector if needed. GPUs can receive up to 75 watts from the motherboard directly. GPUs that need more power (which is most GPUs today) must draw power directly from the PSU via a 6-pin or 8-pin connector.
- Try using a different port. Most graphic cards have several ports for display, such as HDMI, Display Port, and DVI.
Some online sources will recommend baking a dead card to revive it.
Theoretically, this is supposed to melt the solder joints on the card, allowing them to reconnect. I don’t recommend you do this.
It is dangerous and could damage other parts of your computer if something gets shorted out in a critical place on the card.
Have your GPU checked out by a professional. At least they can tell you if you need a new one, but baking is not an alternative to a repair.
But at the end, it may come down to the fact that the graphics card would have to be replaced. If your card is out of warranty and you can’t get a replacement this way, a new replacement is the best solution.
This is the surest way to correct the problem and will breathe new life into your computer’s performance for gaming if your card has aged somewhat.
The good news is that a graphics card is a component that can be obtained from a second-hand purchase or other sources as opposed to a local computer store.
7. Hardware incompatibility
When analyzing the term, not connecting to a monitor, you can also interpret a physical plug incompatibility that doesn’t allow you to plug your monitor’s display cable into the back of a computer.
This can happen after you upgrade a graphics card and have an older monitor with a VGA or DVI plug, which modern graphics cards no longer have.
The same can be true in reverse, where you’ve bought a new monitor with only HDMI or DisplayPort input ports.
Find the plug type online at the end of the monitor’s display cable. Do the same for the graphics card output port on the back of your computer.
How to fix
For this solution, you must order or purchase an adapter or dongle from the right converter or adapter for your monitor.
Once you have established the two connector types, you must purchase the correct solution for your needs.
Before we continue, I wish to make something clear. DVI connectors come in different varieties.
The two main camps are DVI analog, which can easily be adapted to VGA, and DVI digital, which can easily be adapted to HDMI.
However, if you cannot plug one type of DVI connector into another, it generally means that the DVI’s intended signal is different.
So, a DVI analog connector won’t be able to fit a digital DVI port, and vice versa. You will need a special active converter to convert an analog signal to digital or a digital signal to analog.
The same holds true for converting a digital DVI plug to VGA. To do the job, a digital-to-analog converter (DAC) to convert a digital DVI signal to a VGA output must be acquired.
Here is a short list of some common converters you might need. Remember that micro and mini versions of DisplayPort and HDMI exist, which adds another set of variables to these converters or adapters.
DVI to VGA Adapter
This kind of adapter is common and takes an analog DVI plug and adapts it to a VGA socket.
HDMI to VGA Converter (DAC)
This converter will have to convert the digital HDMI signal to analog VGA, and powered converters are usually more commonly available than passive ones that don’t require any power.
HDMI to DVI Adapter or Converter
The HDMI to DVI is most commonly found as an adapter, as shown in the image above. However, an active powered HDMI to DVI will be required to convert the HDMI signal to an analog DVI connector.
DisplayPort to DVI Adapter
Here, we have an example of a DisplayPort to DVI adapter. Once again, this converts the DisplayPort signal to digital DVI, but an active converter will be needed to convert the DisplayPort signal to analog DVI.
