display flicker linked to HDMI/USB-C ports

[zc8]

This began after I plugged the laptop into an external display for the very first time. Which, OF COURSE, was after the warranty expired. The internal laptop display is essentially useless now, unless I plug into an external display. Since I need a portable laptop, that's a problem. The internal display only works when plugged into an external display. This is true when connected via USB-C or HDMI port. Internal display is set to 40Hz. 60Hz makes it worse. All drivers are on latest version. BIOS is up-to-date. Issue happened on Win 10 and Win 11.   Post won't let me attach (public) 40/60Hz video:  https://www.youtube.com/watch?v=L0L2k_LWYsk

[Rainbow23]

Hi @zc8,

Welcome to HP Support Community. 
 

This could be a hardware issue with the display screen and may need repair. 

I suggest that you contact HP Service Center in your location from this weblink: https://support.hp.com/us-en/help/service-center 
Note: Select your country from the dropdown,  enter the city or postal code, select the product and click on search to locate the nearest HP Service center near your location.

Hope this helps.
Take care and have a good day.

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