Laptops forever changed where and how we work, and as great as they are at giving us that freedom, it’s still incredibly useful to plug into a larger monitor (or two) when at my desk. As I get older and my eyesight gets worse, it’s so nice to be able to see everything I need to all at once without having to strain my eyes as much.
However, monitors, like laptops, are simply machines at the end of the day, which means sometimes they don’t always work as expected. Getting a “no display detected” error signal on your monitor is quite frustrating, so I spoke to display makers Asus and ViewSonic to get answers as to why this might happen and how to fix it.
«There are generally no shortcuts or hidden tricks when a user gets a ‘no display detected’ signal from their monitor,» said Jenny Lopez, senior product manager of monitors at ViewSonic. There are a few things you can do, though, ranging from quick connection checks to diving into graphics and system settings, Lopez told me.
So before you head to the top floor and chuck your monitor off a balcony, here are some simple steps to get your monitor working again.
Make sure it’s powered on and connected
The first things you should try are also the easiest: Make sure your monitor has power and check that the cable is connected to your computer correctly. Power cords have a way of working themselves loose, and monitor cables do, too, so check that they’re fully seated. It’s a simple first step, but you might be surprised by how often one of these turns out to be the culprit.
I can’t tell you how much time I’ve spent yelling at my monitor and computer for being stupid and broken, when all along, something was simply not plugged in correctly. And once I spent half an hour troubleshooting why my monitor wasn’t getting power, only to realize I accidentally turned off my surge protector. So, yes, start by checking the power and connections. This is also a good time to power everything off and on again. Sometimes a reboot is all that’s needed to get things working properly again. Also, make sure that if you’re using a docking station or hub, everything there is plugged in correctly as well (and it’s powered on, if necessary).
Check that you’re on the correct input
If everything is plugged in correctly, then check the inputs on your monitor. Most monitors today will have multiple input options for connecting to your computer. But in order for your computer to correctly show on your monitor, the monitor itself will need to be on the correct input.
Most monitors have a physical button that lets you switch the inputs on the monitor itself, but there are a few that might use a remote instead. Either way, whichever input the cable coming out of your computer is connected to on the monitor, that’s the input you’ll need to select for things to show up properly. It’s rare, but on some higher-end monitors, the input options might be buried under a few layers of settings, but in general, switching the input should be relatively straightforward.
The most common type of display connection today is HDMI. Another common input is DisplayPort, or even Mini DisplayPort, but this is typically used for gamers, graphic designers and other content professionals. Though you’ll still find these on laptops, manufacturers have largely switched to USB-C as the display output of choice for its small size and flexibility since it can be used for power, data, video and audio through one thin cable.
However, not all USB-C ports and cables have the same capabilities. For example, the USB-C cable that came with your phone or tablet might only be able to charge devices. Likewise, if you have multiple USB-C ports on your laptop, it’s possible that only one supports display output. Try moving the cable to another USB-C port if that’s the case, and, if possible, use the cable supplied with your monitor or one that you’re certain can be used for display output.
At this point, you should also consider doing a full reset of the monitors settings. Open the on-screen display and look for something that says, «Reset to Initial Settings» or similar. Getting your monitor back to its original settings could remedy the situation, though you’ll have to go back in and redo any changes you made that you actually want, such as power management or color temp.
Read more: What Is USB-C, and What Do All Those Numbers Mean?
Inspect the cable
If you’ve done the first three steps here and still aren’t seeing anything on the screen, then you should physically inspect the cable and the ports themselves. Check for any cuts or fraying near the edges. It’s not uncommon for something to slide over the cable or for it to get crimped and cause damage, particularly in an office environment or if you’ve recently moved your desk around.
Be sure to inspect the ends of the cable as well. No matter which type of display cable it is, there will be little metal pins either in the end of the cable or in the port on the monitor. If any of these pins are bent or damaged, this can cause issues.
Also see: Best HDMI Cables
Test with a different laptop or monitor
If you can’t see any physical damage to the cable or monitor, there might be an issue that isn’t visible. To confirm this, plug your computer into the monitor with a cable you know works for sure. If the new cable works, then you know there was a problem with the old cable. You can also try connecting a different computer or device to the monitor. If you suddenly get a picture, then you know your computer’s connection might be the issue.
If those still don’t work, then try plugging into a different monitor if you have access to one that you know works. Again, if the new monitor works, you’ve found the problem.
Reset and update the software
Once you’ve tried all the other steps listed here, it’s time to look at updating the software. Although software bugs related to displays are uncommon, they’re starting to pop up more frequently, particularly with Nvidia graphics cards.
«Over the last few years, there have been numerous cases of display and graphics card incompatibility, especially at the POST [power-on self-test] stage,» said Asus Senior Technical Product Manager Juan Guerrero. «This means you may not initially see any image until the OS loads. For some users, this can be jarring or confusing, and it can require a VBIOS update.» This has notably been the case for numerous Nvidia-based graphics cards, he added.
Most of the time, updating the software can fix the issue. Start by making sure your computer itself has all available updates installed. Sometimes the updates for your monitor can come from the operating system side, Windows or MacOS, so updating your laptop to the latest version can help.
For Windows users, you’ll sometimes need to update the drivers for your graphics card (GPU) itself. The best way to do this is through the dedicated software for your GPU. Intel, Nvidia, AMD or whoever else made your GPU will include software on your computer to update it to the latest drivers.
Buy a new monitor
If none of the above steps fix the problem, it’s entirely possible that you’ll need a new monitor. Thankfully, it’s not hard to find a good one to meet your needs, whether it’s for office work, gaming or a portable display to move around your house or for travel. There are even some good, cheap monitors available. Plus, monitors seem to be discounted all the time, so it’s fairly easy to find one for less than full price year-round.