Check the cable, the monitor's input setting, and Windows display settings first. With docking stations, the dock's firmware and drivers are a frequent cause, especially DisplayLink docks, which need their own driver.
Common causes
Wrong input on the monitor
The monitor may be set to HDMI while the cable is in DisplayPort, or vice versa.
Cable or adapter problem
Loose cables, cheap adapters, and wrong USB-C cables are common causes.
Display mode
Windows may be set to show on one screen only.
Docking station drivers or firmware
Docks need current firmware, and DisplayLink docks need their own driver.
Graphics driver
An outdated graphics driver can fail to detect external displays.
How to fix it, step by step
- 1
Check cables and the monitor's input
Reseat both ends and use the monitor's menu to select the correct input.
- 2
Press Windows + P
Choose Extend or Duplicate.
- 3
Click Detect in display settings
Go to Settings > System > Display > Multiple displays and select Detect.
- 4
Connect directly instead of through the dock
If it works directly, update the dock's firmware and drivers.
- 5
Update the graphics driver
Install the latest driver from the computer manufacturer.
When to call a technician
We set up workstations with the right docks, cables, and monitors so they work every time someone plugs in — and standardize them across the office.
On-site support across Orange County · see our IT support, managed IT, Microsoft 365 support and cybersecurity services.
Frequently asked questions
Why does my monitor say no signal?
The monitor isn't receiving video, usually because of the wrong input, a loose cable, or Windows not sending to that display.
Can every USB-C port run a monitor?
No. The port must support DisplayPort Alt Mode or Thunderbolt. Look for the DisplayPort or Thunderbolt symbol.
What is DisplayLink?
A technology some docks use to run extra monitors over USB. It requires the DisplayLink driver to be installed.