check video cable

[Grandma-H]

When I shut down my computer I get a message to check video card and or cable. The cable is tight and I've purchased a new computer. Still getting the same messge. Sometimes my screen goes black for a few seconds and then comes back on.

[Echo_Lake]

@grandma
Thank you for posting on the HP Support Community.

I have a few troubleshooting steps we could try to fix the issue:  

Let's perform Windows Update and HP Support Assistant:

To check for updates now, select the Start button, and then go to Settings  > Update & security  > Windows Update, and select Check for updates.Install updates from HP Support Assistant: Go to Download HP Support Assistant to install the tool.

1. To open HP Support Assistant, double-click the HP Support Assistant icon .
2. Click My devices in the top menu, and then click Updates in the My PC or My notebook pane.
3. Click Check for updates and messages to scan for new updates.
4. Review the list of updates. Updates with a yellow information icon are recommended. Updates with a blue information icon are optional.
5. Click the update name for a description, version number, and file size.
6. Select the box next to any updates you want to install, and then click Download and install.

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

[Grandma-H]

I have done everything suggested and am still getting the same message. "Can't find signal imput - check video cable." I only get the message when I am shutting down the computer. The screen goes black and then it shows the message and says it's going to sleep and the message dissappears until the next time I shut down the computer.  I'm wondering if it's just that the computer has shut down, but I've never seen this before with any other montior.