1. Try other HDMI cables. I won't say how many times that helped.
2. Besides the graphics driver, install the Intel chipset driver package.
3. Be sure the HP BIOS is current.
4. All that done or maybe before all this go get a current Linux distro on USB or DVD to boot and test with. I don't learn Linux. I use this in a no-install bootable USB stick to see if the hardware works in another major OS. I've used this advice for over a decade. http://tips.oncomputers.info/archives2004/0401/2004-Jan-11.htm
Be sure it's not in TABLET MODE. Noted at https://h30434.www3.hp.com/t5/Notebook-Video-Display-and-Touch/HDMI-video-and-audio-output-is-not-working-HP-ENVY-x360/td-p/6469798
Hello All,
I am currently using a HP ENVY x360 Convertible with an Intel® UHD Graphics 620 driver built in. A while ago, my computer stopped being able to connect to HDMI devices (including multiple TV's, monitors, and projectors). When I plug in the HDMI cable, the monitor seems to recognize a connection but eventually goes to sleep because there is no HDMI data being sent. I have already tried uninstalling and reinstalling my graphics driver as well as the display monitor driver from device manager to no avail. I have also tried connecting to other monitors with no luck. Any help would be appreciated.
Specs
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-HP ENVY x360 Convertible
-Intel® UHD Graphics 620
-Windows 10 Home version 1803
-HP 25vx 25-inch LED Backlit Monitor (But others have also failed too)
Things I've Already Tried
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-Disabling and Re-enabling Graphics Driver and Monitor Driver
-Uninstalling Graphics and Monitor Drivers and Restarting PC
-Trying other cables and other monitors
-Connecting a different PC to my monitor (which works)
-Making sure the Project (Win + P) is set to Extend (Or any other mode)
I appreciate any and all help and would be happy to provide more information.

Chowhound
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