If your All-In-One has an HDMI, DisplayPort, or Thunderbolt port:

To connect a second monitor to your All-In-One, all you'll need is the appropriate video cable. If your monitor's inputs are different from the output of your All-In-One, you may also need an adapter to convert the format into one compatible with your monitor.

Recommended cables:

• HDMI High Speed Male-Male Cables
• HDMI to VGA adapter (for older monitors)
• HDMI to DVI Cables (for DVI monitors)
• DisplayPort to HDMI Adapter
• DisplayPort to DVI Adapter

All-In-One Dual Monitor Display Settings:

Generally speaking, external monitors can be used in one of three modes:

• Duplicate: Displays the same image on all displays (also called mirroring.)
• Extend: Combines all displays into one shared workspace (also called spanning)
• Projector: Displays an image on the external display, while disabling the built-in display

These can be selected from within OS Display Settings in Windows or macOS.

Troubleshooting an external monitor:

• Try restarting all involved devices
  
  
• Make sure all cabling and hardware is undamaged
  
  
• Check compatibility between all components. Keep in mind that just because a format can be physically adapted doesn't necessarily mean the signal is compatible.
  
  
• Some adapters only work in one direction. For example, DisplayPort to HDMI, or DVI to VGA.
  
  
• Make sure your software is up to date and properly configured - both the operating system and firmware. A firmware update from the manufacturer can sometimes resolve hardware issues.

If you don't have a video-out port, or only have an HDMI-in port:

If your HDMI port is an "Input" port, it cannot be used to connect an external display, but is intended to allow the use of the All-In-One itself as a display. In this case you can use a USB Display Adapter to connect an external monitor. These connect to a USB port, and provide one or more connections for external displays. Although these are typically less capable at 3D tasks, they can run desktop applications and full screen video.

Recommended solutions:

• USB 2.0 to VGA Video Adapter
• USB 2.0 to HDMI Video Adapter
• USB 3.0 to DisplayPort 4K Video Adapter
• All USB Video Adapters

Why can't I use the HDMI port on my HP Envy all-in-one desktop?

The HDMI port on some models of HP all-in-one desktops is for input only. This is handy for when you want to use your desktop as a display for another device such as a video game console or DVD player, but it can preclude the use of a second monitor.

On the HP Envy all-in-one desktop, for example, the "HDMI IN" port is located on the lower left hand side of the monitor. To use it, just plug in your HDMI output device and switch the computer from PC mode to HDMI mode using the HDMI IN button under the bottom left hand side of the display. To change back to PC mode, just hold the HDMI IN button.

Why aren't USB-C alt modes working on my HP Envy?

Although advertised as a capability, a number of HP Envy systems of various types appear to to be unable to output video through their USB-C port.

In some cases this can be due to a limitation of the hardware. Alt Modes are used to transmit native HDMI or DisplayPort signals over a USB-C cable, and allow for it to be directly connected to a display. However to enable this feature, the computer must have the appropriate hardware. Some HP Envy systems only support the DisplayPort alt mode, and must be used with DisplayPort displays, or adapted to the proper format.

USB-C Video Adapters:

• USB-C to DisplayPort Cable
• USB-C to HDMI Cable
• USB-C to VGA Cable
• DisplayPort to HDMI Adapter

In other cases it appears that the USB-C port is not capable of video output at all. This may be due to hardware issues, or may be caused by a driver or firmware incompatibility.

HP does guarantee that any USB-C port advertised as "Thunderbolt 3" compatible will support standard Alt Modes, and can be adapted directly to HDMI or DisplayPort.

If your USB-C port doesn't appear capable of outputting video, you're not out of luck! You can still use an active USB to video adapter.

USB Video Adapters:

• USB 2.0 to VGA Video Adapter
• USB 2.0 to HDMI Video Adapter
• USB 3.0 to DisplayPort 4K Video Adapter
• All USB Video Adapters

Does my HP Envy need a dual monitor adapter?

To connect additional monitors to your all-in-one, you just need available ports such as HDMI, DisplayPort, or VGA. If you have none of these available, or if the port is intended for input only, you can use a USB Display Adapter to connect multiple additional monitors.

Do you have a giant chart of HP All-In-Ones that would indicate what ports and controls I might have?

As luck would have it, we do. This chart shows which models have video in/out capability, and whether they have a source select button.

+ Show/Hide Table!