USB 3.0 to HDMI External Multi Monitor Video Graphics Adapter for Mac & PC - DisplayLink Certified - HD 1080p

You may have heard of USB video adapters, and have been wondering what they are, and whether or not they will work in your setup.

USB video adapters are devices that take one USB port and go to one or many video connections, such as VGA, DVI, HDMI or DisplayPort.  This is useful if you would like to add an additional display to your computer setup, but are out of video connections on your computer. 

USB video adapters allow you to mirror or duplicate your display, so the same windows are shown on all of your displays, or extend your desktop, so that you can have different windows on each display.

So what do you need to know before you purchase a USB video adapter?

• USB video adapters require the computer to have a free USB port.
• Check which video connections your display has, and select the appropriate USB video adapter.
• Ensure that the USB video adapter is compatible with your operating system.
• USB video adapters require your video card to be able to handle an additional display.  This is because USB video adapters work with your onboard or dedicated video card to drive additional displays.  For this reason you are advised to confirm this with your video card manufacturer. 
• Consider what you will be doing on the additional display.  If you are looking to perform less graphically intensive activities like using Microsoft Office, email, or basic web surfing, you can use any USB video adapter.  If you are looking to perform more graphically intensive activities like high end photo or video editing, you want a USB video adapter with dedicated memory. 

There are a few other important things to note:

• When using multiple USB video adapters on the same computer, they need to use the same chipset family.  For example, MCT/Trigger, DisplayLink or Fresco.  Note: How many adapters you can use depends on the SKU.
• You may not be able to use a USB video adapter with an All-In-One computer.  These computers are almost always hardwired to only accept a single display.
• You may not be able to use a USB video adapter with a touchscreen computer or display.  A mixture of touchscreen and non-touchscreen devices can conflict with the video card. 
• You should not use a USB video adapter to play video games.  They are not designed for use with video games, and their performance with them is poor at best.

You can use an external display or projector with a Mac notebook while its built-in display is closed. This is known as "clamshell" or "closed display" mode.

Clamshell mode requires that the following devices are connected to the Mac notebook: 

• A power adapter.
• An external keyboard, mouse, or trackpad.
• An external display.

macOS does not see DisplayLink displays as external displays, therefore this criteria is not met and clamshell mode cannot be enabled when a DisplayLink adapter is the only external display connected to the computer.