2nd Monitor connected to All In One flickers off and on

[epete111]

I have a second monitor connected to my HP ENVY Curved All-in-One - 34-b135se HDMI Out port.  Recently the display would go out for a few seconds and come back on.  Now it is constantly flickering off and on.

I have replaced the monitor and problem occurs on the replaced monitor

I have replaced the HDMI Cable and problem still occurs

cables are secure and not loose

The main monitor on the PC works fine.

I was wondering if this could be the graphics card , but I would think that would impact both monitors.

I assume the HDMI connector is soldered directly on the Motherboard so there is nothing that could come loose internally.  (Just a guess).

I have purchased an Anker brand USB to HDMI interface that should arrive soon and hoping I can just use that to get around the problem.

Anyone have any other ideas on what I can try to troubleshoot and repair?

[Prométhée]

hi

"I assume the HDMI connector is soldered directly on the Motherboard so there is nothing that could come loose internally. (Just a guess)."

 particular here, it seems
you obviously have a graphics card We see an m2 type slot:

HP ENVY Curved 34-b135se All-in-One Desktop PC Product Specifications

NVIDIA GeForce GTX 1050 dGPU (4 GB)

Canard motherboard specifications.

so see if you can remove it, and test on the built-in
but it is rather delicate, this type of machine

before try reinstalling the driver

https://support.hp.com/us-en/drivers/selfservice/hp-envy-curved-34-b100-all-in-one-desktop-pc-series...

[epete111]

ok, thanks.  From software I can select either the internal Intel graphics or the NVDIA.  It seems to have problems with both but i am not sure that selection one over the other in sw actually does just that.

I  will try the driver then if the doesn't work, I will try and remove the card.  I have already disassembled a couple years ago to add a larger drive so I am somewhat familiar and can be gentle with the card.

[epete111]

I updated the driver and no luck on fixing the HDMI out intermittent signal.  There was a period yesterday where the Signal was lost for several hours, then it came back  with periodic flickering off/on again.

My ANKER USB-C to HDMI adapter came in yesterday and the display works with the adapter.  At this point, a $13 solution on a fairly expensive 4 year old PC may be all I need.  Not sure if it is worth opening the PC for additional troubleshooting and risk damage from tinkering around.

This is one of the biggest issues I have with All In Ones.  Something malfunctions and it becomes difficult to fix.  Then you end up with a mostly good but unusable PC.  But the ability to avoid the larger Desktop PC with interconnect cables was attractive.  

Anyway, when the PC eventually dies, I may opt for a small form factor PC and connect it to the HDMI Video in (assuming that port is not intermittent as well).  Question:  When the Video Input button on the back of the PC is pressed, is the CPU and other All In One devices still drawing power?  Maybe I could put the PC in sleep mode and the monitor could then be used without drawing unneeded power.

[Prométhée]

I do not know at all ..
The option must allow the monitor to be used with another device
but I don't know which element continues to work, even if in this case the computer is not completely on the way..
Only the screen function should work, but I haven't seen any indication of this

Indeed, too bad, but taking the risk of dismantling everything, may not be valid indeed..
If it works like that, it's up to you, but I think that the risk of breaking is actually too great.

[epete111]

Thanks for the good advice.  So I will use with my USB-C to HDMI Adapter since that solution works for me.  I should eb able to get several more years out of this system with this quick fix and not opening the unit.