Question Plugging in LGTV disables other screens (except one) (it is complicated)

Jan 27, 2024
3
0
10
Good day,

I am hoping that one of you lovely people might help me from my current insanity. The issue is as follows: I use a 4 monitor setup, sort of unusual, with two monitors on the desk, a graphical tablet in front of them and an LG C11 TV on the side. Now, this exact same setup worked perfectly on my old PC, meaning the two desk monitors would turn on, with the TV and the tablet remaining switched off until I would need them - turning them on would simply extend the display and I could do my work in peace. However, at the end of last year, I have built a new PC and since then, there have been...issues.

When I power the PC back on after turning it off, all screens except one of the desk ones are set to "Disconnect this screen" in Windows. Therefore, they are visible in the windows screen settings, but remain black. Now, they can be turned back on without problems, but the next time I power my PC down, they will be disconnected again. Disconnecting the LGTV from the HDMI port fixes the issue, but I would like to avoid crawling down into the convoluted mess of cables under my desk every time I want to turn the damn screen on.
As I have mentioned, this same exact setup worked flawlessly on my old PC. I have tried to plug my old graphics card (RTX 2080) into my new rig and it worked just fine, which leads me to believe the issue is with the GPU.

What I have tried (and it didn’t work):
- Returning the card. They sent it to some repairman, who "repaired" it and sent it back. Didn’t make any difference.
- Using a HDMI to Displayport converter (the TV only has HDMI ports). Didnt do anything except (predictably) disable G-SYNC.
- Connecting some of the monitors to integrated graphics. Not sure why I even tried this, but either way, integrated CPU graphics being enabled/disabled/wiped from existence/connected/disconnected etc. does not make any difference.
- Clean installing every concievable version of the GPU driver and even wiping it using DDU.
- Running windows integrity tests, reinstalling windows.
- Messing with display settings in both windows and Nvidia control panel.
- Messing with settings on the displays/TV themselves.
- Disabling/enabling fast startup in power settings
- Updating BIOS on the GPU and the motherboard.
- Using different cables for every monitor.
- Disconnecting every USB device.
- Straight up begging the TV to work normally again, bringing it sacrifices of screws and screen cleaner.

There might be more. I have been googling for days. My sanity is slipping.

Current (new) PC specs:
CPU: Intel core i9-14900K
GPU: GIGABYTE WINDFORCE RTX 4090
SSD: WD Black SN850X, 2TB
RAM: G skill Ripjaws 6400 mhz - DDR5, 64GB
MBD: ASROCK TAICHI LITE Z790
OS: WINDOWS 11
PSU: be quiet! 1200W Pure Power

If you swap the 4090 for my old 2080 super, keeping everything else the same, it works. If I keep all the monitors running at all times, the issue doesn’t appear (but that is not an option).

The screens: On the desk 27LG850 (2K/144Hz) + Samsung U28E590 (4K, 60Hz), in front of them Wacom Cintiq 24 Pro (4K/60Hz), on the side LG C11 (4K, 120Hz). An odd setup, but it used to worked fine.

Will be grateful for suggestions. If there is any info I left out, let me know.

Thank you.

A small edit: If I set the LGTV to 60Hz, everything works normally. Doesn’t really solve the issue, but might be a clue.

Edit: A video
View: https://youtu.be/hIyc5u_TdWY
 
Last edited:
Jan 27, 2024
3
0
10
Das haben sowohl das LGTV als auch die Einstellungen gesagt. Ziemlich sicher. (Tut mir leid, mein Deutsch ist nur so gut wie Google Translate)


English:
That is what both the LGTV and the settings said. Quite sure. (Sorry, my German is only as good as Google translate)