Have you been slapped with a “No Signal” screen on plugging in your portable monitor to your laptop? It doesn’t necessarily mean you bought a faulty monitor. Let’s make it clear; don’t confuse “no response” with a “No Signal” problem.
Portable monitors are excellent as they make it easier to multitask when you have a lot to do with limited time. Besides, they let you carry them anywhere so you can continue with your work. If you recently encountered a challenge connecting your monitor to a device, understanding how they work can help you troubleshoot the problem faster.
How Do Portable Monitors Transmit Video Signals?
The main cause of a “No Signal” notification on your display is an indication that your monitor isn’t communicating with your video source device. The device can be a laptop, gaming console, Nintendo Switch, or smartphone.
Although not necessary, understanding how data is transmitted from your device to your portable monitor can play a significant role in helping you identify and fix the problem.
Types of data connectivity ports on Portable monitors
A portable monitor transmits data through ports that connect to a notebook, smartphone, or device to output video signals.
Today’s portable monitors come with various ports, each serving a different function. With the right monitor, you can enjoy an incredibly smooth media streaming experience, whether listening to music, watching videos, or playing games. Most modern portable monitors transmit video and audio signals through DisplayPort, HDMI, or USB-C.
Choosing the correct port type will mostly depend on your needs and is a big game-changer when you want to experience a smooth, seamless viewing experience.
HDMI Port
HDMI (high-definition multimedia interface) has established itself as the standard in home entertainment, and it’s found in every major brand of TV, Blu-Ray player, video game system, and home theater.
It allows you to transmit uncompressed video, audio, and even data over a single cable. It’s the standard for HD quality streaming and has been adopted by most prominent companies in the media industry.
While most of us assume that there is only a single HDMI cable type, that’s far from the truth. There exist four types of HDMI cables. But the most commonly found on portable monitors is the HDMI Standard, often shared in displays with resolutions of up to 1080p.
Higher-resolution portable monitors like the 4K use HDMI High Speed. This HDMI type is regarded as a fast transmitting connection, capable of handling transmission speeds of up to 10.2Gbps.
The next on the list is the HDMI Premium High Speed, which is commonly used for HDR-enabled portable monitors. You’ll find this HDMI on Lenovo ThinkVision M14 and UPERFECT S devices, released in 2020.
If you’re lucky enough to have an 8K portable monitor, know that it uses the HDMI Ultra High Speed to transmit data. This HDMI type can support uncompressed video data with speeds of up to 48GBps.
Besides standard, there are also three different HDMI shapes: HDMI standard port, mini HDMI port, and micro HDMI port. The mini HDMI port is the most commonly used in portable monitors due to its slim design.
DisplayPort
Like HDMI, DisplayPort cannot support power transmission to a portable display, hence used purposely for video signal transmission. It was launched in 2008 and is often found on a premium-level mobile monitor. As such, it’s primarily reserved for transmitting high data speeds, such as when gaming or editing video. In general, it’s ideal for handling highly intensive duties.
At the moment, there exist three types of DisplayPort. DisplayPort 1.2 is the entry-level and can support display resolutions from 3840p or 4K and a refresh rate of 60Hz. Most portative monitors will have this type of DP in a smaller size, called mini DisplayPort or mini DP.
DisplayPort 1.3 is often used for transmitting 8K video resolution transmitted at a refresh rate of 30Hz. A portable screen with an 8K resolution, 60Hz refresh rate, and HDR support will often have DisplayPort 1.4. It’s the fastest and can support the highest graphic setting requirements, such as when playing high-quality modern games.
USB-C
USB Type C, often named USB-C or Type-C, is one of the best things that ever happened to the world of data transmission. That’s because it’s capable of transmitting high-speed data and power simultaneously when it comes to USB 3.1 or later, also called full function/feature Type-C. Most modern portable monitors will have at least two USB-C ports in place of DisplayPort and HDMI.
USB-C is known for its great versatility as it is reversible; you can plug it in any direction and still work. Due to this great advantage, USB-C ports make it easier to use portable monitors with your laptop, tablet, smart phone, and gaming console.
Now that we’ve familiarized ourselves with how portable monitors receive data from input devices, let’s jump to how to connect your portable monitor to your laptop.
How To connect your Portable Monitor to a Laptop
Sometimes the “No Signal” issue could be due to an improper connection of an external monitor to your device. Even though portable monitors can connect to devices other than laptops, we’ll use the latter as a standard. Once you get the hang of it, you’ll be able to connect it to any other device.
USB-C to USB-C Connection
If you want a trouble-free way of connecting your portable monitor to a video output device, USB-C to USB-C connection is the best. This connection requires only a single cable to transmit video signals and power simultaneously.
USB-C to USB-C connection is ideal for connecting your laptop, android, or Apple device to your second monitor. Make sure your notebook has a thunderbolt 3.0 standard or later, or USB Type-C 3.1 or later. You can turn to your device provider for help or check our model list here if you don’t know.
Most current portable monitors often include the USB-C to USB-C cable. Connect it to the correct Type-C port on the monitor because sometimes there is a Type-C port for power only, marked as a PD port.
If you’ve made your connections properly, your portable monitor power indicator lights green, and the “No Display” notification persists, you should proceed to troubleshoot.
Connecting with mini-HDMI, HDMI, or DisplayPort
If your laptop has no Thunder Bolt or USB-C port, you can transmit video signals using a mini-HDMI, HDMI, or a DisplayPort, depending on what ports the second portable screen has. Remember to power with a wall socket outlet if your portable display does not has an in-built battery.
The Most Obvious Reasons for Portable Monitors Not to Work
As highlighted, the causes of a monitor not working as required could be due to a no response or second monitor not detected.
No response from your portable monitor means that the display is black as if it is not plugged into your laptop (when using one cable connecting) or does not have a power source. In such a case, the power indicator LED is usually off. The straightforward solution is to ensure that it’s plugged into your device (when using one cable connecting) or a wall socket outlet.
Portable monitor not receiving power
Before we jump into the deep troubleshooting bit, the problem of a mobile monitor having no response could be a matter of power input. Checking whether your monitor is receiving power should be your first action. Thankfully, it’s pretty simple to check when dealing with portable screens.
For a monitor that uses the USB-C for power, ensure it’s connected with the wall charger and the power indicator lights green to show that it is receiving power. If not, it will have no lights on. For a battery-powered monitor, ensure the battery is fully charged before connecting.
“No Signal” message on display with green light power indicator
If your portable monitor is plugged in and now shows the “No signal” message, you should proceed to fix the issue. There are several reasons why that could be happening. If you’re a hands-on guy and don’t mind troubleshooting what might be the problem, this guide will explain a few of the possible causes of the lack of signal and how to resolve them.
Troubleshooting The “No Signal” Problem on Portable Monitors
If you managed to pass the no response problem, which is often caused by a lack of power input, your portable monitor may or may not be working. The “No Signal” message will be shown on the display if it is plugged into your device and is receiving power as expected.
The following are some of the main causes of a “No signal” response on a portable monitor and how to fix them.
Port Compatibility Issues
As we mentioned before, portable monitors connect to devices through USB Type C, HDMI, and other ports. If connecting to a laptop using USB-C with one cable, ensure that you have a Thunderbolt 3 or above, or USB-C 3.1 or later.
If you’re using a smartphone to connect to your portable monitor, ensure it has a USB-C 3.1 or later. USB 3.1 ports are upgraded USBs capable of transmitting both power and data. Most modern smartphones will have USB-C ports, but few of them have video output functions. Phone brands that have upgraded the Type-C port to full feature function are mostly found in the Samsung Galaxy series, Huawei Mate series, and OnePlus.
Many users are using the second external screen with computers and PCs. If the device is not yet upgraded to an HDMI port for video output, they need to convert VGA or DVI to HDMI. If that’s the case, ensure your adapter can support VGA to HDMI compatibility because some adapters offer only one-way connectivity, HDMI to VGA.
You may also face the “No Signal” message when trying to connect your portable screen display to a Nintendo Switch console via a USB-C to USB-C cable. In such a case, ensure the monitor is powered via the Switch charger rather than the monitor’s charger. If you want a more stable connection, you may use the HDMI port of the Switch dock.
Power Supply Insufficiency
When connecting a single USB-C cable, your portable monitor gets power from your device. Sometimes the power might not be sufficient to enable the monitor to function optimally.
Mainly, the power insufficiency is caused by your device limiting the USB-C power output. When the display is powered on, it requires a high power current and sometimes exceeds the device’s supply, especially for a smartphone.
Another cause of low power supply can also be the higher power requirement. Laptop external monitors with high resolutions such as 4K or wider sizes like 17.3 inches will require more power input than what a device can give.
In these cases, you are suggested to go for a portable monitor with an internal battery or an external power input. However, if you cannot find a power socket, a power bank might also work.
Usually, 1080p portable monitors require 5V 2A power input when connected to a laptop. You can choose a Power Delivery (PD) power bank to supply the required power rating using a smartphone. For a 4K resolution monitor, you’ll have to connect it to a PD power bank to get the minimum requirement to support performance.
Wrong Display Settings
Computer monitors out-of-the-box may or may not have the appropriate settings to support plug and play. The most likely cause is that the auto-search functionality is not turned on, and the monitor may need to be directed to the source of the input signal.
Select your monitor’s control panel and find the input signal source to set it right. Note that if you had used a USB-C connection during your last session and in your subsequent session you’re using HDMI, you’d need to change the setting.
Thanks to the portable display technology, the Autosearch setting is build-in the monitor, and it will refresh and connect using your new connection medium. Should this bear no result, select the appropriate setting, either HDMI, MiniDisplay, or VGA, from the input source screen, and your monitor should light up.
Sometimes, the wrong settings could be on your laptop. If you had previously connected to a second screen and did exit with the Show Desktop Only on 1 or 2, you will also get the “No signal” message. Check your laptop and change the display setting to Duplicate or Extend these Displays.
Obsolete Graphics Driver on your Laptop
If your laptop doesn’t recognize a second monitor, the problem could be the graphic driver. Doing an update allows your computer to improve the display resolution as well as identify any secondary monitor plugged in.
Updating the graphic driver is simple enough if you’re using a Windows OS. Microsoft often releases new updates from time to time, and your PC downloads them automatically and schedules a time to install them. If you haven’t restarted your PC for some time and have a notification message that it has pending updates, a restart might do the magic.
Apart from a restart, you can also check for updates manually. To do this:
- Go to Windows Settings-> Updates & Security.
- Select the Windows Update option to check whether there are any pending updates.
- If none is listed, click the Check for Update button.
Running Windows update check won’t let you pick the updates to install. But the OS will choose the required updates and install them for you.
Manually updating the graphics driver on Windows
If you recently did a Windows update, you may then require to update the graphics driver manually. Using the Device Manager utility, you can search the web for the graphics driver updates suitable for your laptop’s graphic card. To do this:
- Simultaneously press the Windows Start Key and R to start the Windows Run box.
- type in devmgmt.MSC then press the enter key to open Windows Device Manager.
- On the Device Manager window, scroll to the Display adapters and expand it to list the dedicated and integrated graphics drivers.
- Click to select a graphic driver, then right-click and select Update Driver.
- On the pop-up window, choose Search automatically for drivers. The OS will auto search for the right graphic drivers, download, and install them.
Updating graphics driver on MacBook
Mac OS usually comes with its graphic display driver built-in. That means you cannot install the graphic driver update only, but you’ll need to update the whole operating system. To do this:
- Click the Apple logo to open the menu.
- Click the “Software Update” option.
- Mac OS will indicate if there are updates available that need to be installed. If a graphic driver update is available, it will be included as part of the OS update.
When your laptop’s graphic driver is up to date and everything is in order, the portable monitor should be able to light up as expected.
Port and Cable Connectivity issues
After trying out every suggestion given above to sort out the “No Signal” problem without avail, it’s time to confirm if the connection ports and cables you’re using are working fine.
Faulty connection ports and cables
Whether a USB-C or HDMI port, they can develop problems that might render connectivity to a portable monitor impossible. To ascertain if that is the case, try using the laptop’s ports with another device. If it’s an HDMI port, try to connect to a TV HDMI port using an HDMI cable. If it works well, that cancels out the suspicion of a faulty HDMI.
Alternatively, you can try connecting the portable monitor to a different laptop to ascertain whether your laptop’s ports are faulty. If it does work, then you know that there is an issue with that specific port. If it doesn’t, you can try to connect your laptop to a different portable monitor, which will rule out all possible issues on both your laptop and portable monitor ports.
Faulty connection cables
Sometimes, the issue could be with your connection cables. After prolonged use, a cable may become loose when connecting to a USB port. You can try fumbling it while still connected to the port to see if your screen will light up.
If that doesn’t work, the next thing is to try and test the cables. Test the USB-C and HDMI cables on different laptops and portable monitors. If all fail, you might want to replace them. Alternatively, you may use an android app known as USBCheck to determine if a USB-C cable is working or not.
Faulty portable monitor ports
Another possibility is that your monitor’s port may be broken or faulty. In that case, things may become very complex for you to fix. But first, you can test the ports using a different cable and a laptop. If it doesn’t light up, then we may conclude that the ports are faulty.
For a portable second display under warranty, you can arrange for the supplier to fix or replace it, depending on the terms and conditions of the purchase.
Summary
Portable monitor for laptop is the easiest way to multitask to get many things done in a fraction of time. While these monitors are ideal for use both outdoors and indoors, it can sometimes be troublesome to get them to work with your device, especially if it’s your first time using one.
For starters, most portable monitors can start right out of the box without doing any configurations as long as the connections are made right. If you can’t get your second monitor to work, first check to ensure that the display is receiving power. This is applicable primarily if the monitor has no response or a black screen.
For the “No Signal” message, second monitor not detected,it is an indication that the portable monitor is powered but not receiving video signals from your device. The above troubleshooting tips given should help you to get it to work. In a situation where all efforts bear no positive result, you may opt to return it to the supplier if it’s still under warranty.