
An extended desktop, not to be confused with a mirrored display, is when you make your laptop or desktop PC have its user interface desktop extend beyond one screen. This is a handy feature available in many Windows and Mac OS operating systems. You just need to adjust your screen settings in accordance with the number of monitors you have, which can go from two to three monitors.
With that said, how do you extend your monitor if you only have one VGA port on your workstation or notebook PC? How to extend the monitor with one VGA port? Here’s what you need to know.
What Does VGA Desktop Extension Entail?
An extended desktop that spreads over two or more monitors allows you to do things like play multiple programs at the same time from one monitor to another. There’s a primary desktop and the extended desktop, typically one that doesn’t contain any icons of executable programs found on the primary desktop, with it being empty and everything.
- Games, Video Editing, and Graphic Design: As a graphic artist, you can also extend your photo editing or vector graphics program so you’d have a wider canvas. It’s commonly used in either gaming for a lengthier U.I. or in video editing, with the video timeline going all the way to the second or third monitor.
- Extended or Tiled Wallpaper: Usually, the wallpaper tiles or extends outwards from your primary desktop unless you’ve availed of desktop wallpaper made specifically for extended monitor displays. That wallpaper should be free of icons and shortcuts for programs found on your primary desktop.
- Multi-Port Graphics or Video Card: Some say a VGA splitter isn’t what you need. Instead, you need a graphics card with an extra VGA port on your notebook or workstation PC to allow for a display extension to happen, they claim. You shouldn’t use things like a VGA or HDMI splitter to extend your desktop across multiple monitors.

How to Extend Monitor with One VGA Port?
Does a VGA Splitter Work or Not?
A VGA splitter works when it comes to adding an extra monitor or two to your desktop or laptop PC. It should help you mirror the same user interface as your operating system would allow. A splitter doesn’t (or isn’t supposed to) support extended desktops. All it does is mirror the same images or desktop found on your primary desktop on multiple monitors.
Allegedly, based on how desktop extensions used to be done, a VGA splitter shouldn’t work in splitting the feed and turning the second signal into a desktop extension. There was a need for a special graphics or video card with multiple video outputs in order for the operating system you’re using to use the split signal for desktop extension purposes. From there, you can link an HDMI or turn a DVI connection to a VGA one with an adapter.
However, thanks to the advances made since Windows 8 and 8.1, this might not be the case anymore. Through a combination of more advanced operating systems and more advanced graphics cards, all you really need is a Dual Monitor VGA Y-Splitter Cable to make the desktop extension a reality. From there, just configure your desktop to do the extension instead of mirroring and you’re good to go.
The VGA Y-Cable Is The Missing Link
Desktop extensions are so ubiquitous an option in Windows 8 that there’s troubleshooting in case you accidentally extend your monitor on your projector connection for HDMI, resulting in what looks like an empty desktop with no program icons on its wallpaper. With that said, you need a special VGA splitter that can specifically work with Windows 8 or similar operating systems in order to extend a desktop display.
You should look for a VGA Y-Splitter Cable that allows two separate VGA monitors to extend your desktop display on a single default video graphics card and its lone VGA port. When it first came out, it can only do desktop extensions on Dell-branded PCs. However, this was way back during the Windows XP era and probably required a special driver to work. You can use this cable with Windows 8 or 10, to work on the more advanced default graphic cards of the decade.
How to Configure an Extended Desktop
In order to test if you have a desktop or laptop PC with a working extended desktop feature, do the following (for Windows 8).
- Plug VGA Y-Splitter: First off, turn off your PC then plug the VGA Y-splitter on your PC (primary desktop) and your multiple monitors (secondary desktop and even a tertiary desktop if you wish). Although your PC is plug & play, this 30-year-old technology is not hot-swappable.
- Start Button and Control Panel: Once you’ve turned on your machine and it recognizes the monitors, go to the Start button and select the Control Panel. From here, select the option known as Adjust Screen Resolution in the tab for Personalization.
- Detect Button and Extend Displays: It’s at this window that you can choose your Extend Displays option. But first, you need to click the Detect Button to double-check if the computer even detects the monitors you just connected to it. From there, just click Extend Displays and then save changes.
- Multiple Displays vs. Extend Displays: The Multiple Displays option allows you to mirror the same display as your primary display. This is handy when attaching a VGA projector to your computer for the sake of doing presentations or watching movies. The Extend Displays option allows you to extend your primary desktop to the other monitor to make it longer. You can even extend it as far as a third or fourth monitor if you have enough splitters available.
In a Nutshell
In order to connect your monitor to your desktop or laptop PC, you used to need two ports from the same advanced graphics card for VGA, HDMI, DVI, and DP for the desktop extension to work beyond mere screen mirroring.
This should typically be the case for VGA monitor extensions, but thanks to advancements in desktop extensions from operating systems like Windows 8 and VGA splitters like the VGA Y-Splitter cable (preferably one with extra USB support to make the connection more solid), you can do a desktop extension on a single VGA port without getting a special video card to accept it. Indeed, technology marches on.
References:
- “How to extend display on two monitors with VGA splitter“, SuperUser.com, December 21, 2017
- “How do I connect two monitors to a PC which has only one VGA port?“, Quora, April 5, 2018
- EZSILENT HUSTLE, “How To Setup Dual Monitors with HDMI And VGA 2020“, YouTube.com, August 13, 2018
- “How do I add Monitor for Extended Display: Only one VGA Port“, TenForums.com, October 25, 2018
- Zach Lazzari, “How to Use a Dual Video Monitor VGA Y-Splitter Cable“, Small Busines Chron, February 12, 2019
- “How do You Set Up Extended Desktop with Only One VGA Output from the Computer“, Cmple.com, Retrieved November 27, 2020