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How to Determine Your USB-C Port Video Capabilities

Last Update: August 20th, 2026
Article ID: 3185059

Understanding your laptop's video output capabilities is essential when connecting to external displays. This guide will help you identify what video technologies your laptop supports and how to find the relevant information.

Common USB-C Video Output Technologies

Modern laptops commonly use one or more of the following technologies to transmit video to external monitors:

Thunderbolt and USB4

  • DisplayPort Tunneling: DisplayPort video data packets are transmitted within Thunderbolt/USB4 data packets from the computer to a Thunderbolt or USB4 docking station, graphics adapter or display.
  • Multi-Display supported resolutions
    • Thunderbolt 3 enables up to two DisplayPort 1.2 streams, supporting up to two 4K 60Hz external displays.
    • Thunderbolt 4 & USB4 enables two DisplayPort 1.4 streams, supporting a single 8K display, or upto two 4K 60Hz displays
    • Thunderbolt 5 & USB4 v2 enables two DisplayPort 2.1 streams, optionally with asymmetric bandwidth up to 120Gbps enabling up to two 8K displays, or two 4K displays with high refresh rates (120Hz or higher).
  • Identifying the port:
    • Thunderbolt Uses a USB-C connector and features a lightning bolt symbol next to the port.
    • USB4 Uses a USB-C connector and generally has the USB4 logo next to the port.
thunderbolt ports on a system photo

Note: An example of Thunderbolt 3 ports

USB-C DisplayPort "Alt Mode"

  • DisplayPort video data is transmitted directly from the USB-C port, taking up two or four of the USB SuperSpeed data lines.
  • DisplayPort 1.2 capable hosts can support a single 4K 60Hz display and USB 2.0 data, or single 4K 30Hz display and USB 10Gbps data (for example when using a docking station).
  • DisplayPort 1.4 capable hosts can support a single 8K 30Hz/4K 120Hz display and USB 2.0 data, or a single 4K 60Hz display and USB 10Gbps data.
  • Often marked with a DisplayPort ("DP") symbol, but this feature may also be specified in your system's documentation.
usb-c port on a system photo

Note: An example of a USB-C port with DisplayPort capabilities

How to Identify Your Laptop's Video Capabilities

To determine what video technologies your laptop supports, follow these steps:

1. Check Your Laptop's User Manual:

  • Locate your laptop's user manual (often available online from the manufacturer's support site).
  • Search for keywords like "Thunderbolt," "DisplayPort Alt Mode," or "video output capabilities."
manufacturer user manual example image

2. Visit the Manufacturer's Website:

  • Go to the support page for your laptop model and find the technical specifications section.
  • Look for details on Thunderbolt or USB-C video capabilities.
manufacturer port specifications example image

3. Inspect Your Laptop's Ports:

  • Check for identifying symbols next to USB-C ports:
    • Thunderbolt ports may have a lightning bolt symbol.
    • DisplayPort Alt Mode may be marked with a "DP" icon.

What if I do not have the above technologies?

USB 3.0 (Type-A) and Display Expansion

While USB 3.0 (Type-A) ports do not support native video output, they can still be used to extend to two or more displays using software-based solutions like DisplayLink or Silicon Motion's InstantView. These technologies enable video through USB-A ports by utilizing dedicated drivers and software.

If your laptop lacks Thunderbolt or USB-C video capabilities, DisplayLink or InstantView may be a viable alternative for expanding your display setup. A few other things to consider:

  • Not all USB-C ports support video output. Checking your laptop's documentation is crucial to confirm this capability.
  • Thunderbolt ports are backward compatible with USB-C DisplayPort Alt Mode but provide enhanced performance and flexibility.

If you have any questions please feel free to contact us at support@plugable.com and we'll be happy to help!