HDMI devices receive no signal

Hello, this is my first post of this kind since ages, but at this point I'm beyond frustrated and confused.
Sometime last year I noticed I couldn't connect my laptop to my TV via HDMI when it was never an issue before. The tv recognized that something was plugged in, but it failed to receive signal no matter what I tried. I never pursued that issue as it wasn't very important to me.

It is important now, because I can't connect my new graphic tablet (Cintiq 16) without wrestling with it for a few hours every time.
Let me summarize what I deal with:
-tablet recognizes it is connected via hdmi, but receives no signal
-restarts, power cycling, GPU driver reinstallation don't help.
-I managed to kickstart and use it a couple of times however it seems to be random at times- i once managed to make it work after uninstalling my GPU from the Device Manager, but next time it didn't work. Another time it started working the moment I uninstalled PCIE Root Complex. It didn't work next time. I've tried this with a lot of components, I didn't manage to narrow down what really works.
-Once it works, the tablet is fine if I unplug the HDMI and plug it back in, but sometimes it will stop working after a few days of not being unplugged even once, as if the system forgets it.

I've been scouring the Internet for any hints and I've used up all my options for now. None of the tricks work.
I'm somewhat convinced that it's not the HDMI port itself causing problems. But like I said, I'm lost and I have run out of steam to look any further- I need advice. I'll be really grateful for any ideas as to where to look next.

Windows 10 Home 64-bit (10.0, Build 19042) (19041.vb_release.191206-1406)
OMEN by HP 15-ce0xx
NVIDIA GeForce GTX 1060 with Max-Q Design
Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz 2.81 GHz

My guess is that Windows update back in last year updated the driver for you NVIDIA GPU and that resulted in things not working.

Have you tried using Device Manager to Roll back the driver for the GPU to a previous version? It's worth a shot.

Hello,
yes that was my guess as well. No effect. For now I'm assuming it's a hardware fault, but I have no idea how to make sure about it, and whether it's the GPU or the port itself. I was wondering if there are any conflicts between the system and GPU drivers, that was my first guess. It's strange that I managed to get signal a few times since I started, but now it just won't work. I even thought that maybe my SSD or HDD are going bad but the SSD isn't even a year old and both are in good condition, no errors or bad sectors.

Thank you for your replies.
Of course, I've tried different cables and different displays, with the same result.

Clean Boot made no difference as well. And I don't seem to even have those two updates installed, the oldest Cumulative Update I have is from July 2020 (KB4566785).