I am about to pull what little hair I have left out. I've spent so many hours building this rig the past month and it all came to a halt yesterday. I am looking for any suggestions or for a more appropriate place to post this.I just recently setup a triple screen racing rig and the third screen is not working for me. Windows and Geforce Control Panel will see that it is there but there is no image and there are no settings to adjust. In Windows display settings it will show my 1 and 2 monitors at normal size but 3 will be this little square on the right. Windows will make the sound like I just connected a device but you will hear a disconnect sound seconds later and it will do this on loop until I pull the display cable from the GPU. I am using displayports on my GPU and it seems that port 1 and 2 will be fine but when I connect to port 3 the problem starts. I have confirmed port 3 does work by having only one monitor connected to it. 
 
Here's all of the troubleshooting I have done thus far:

Update BIOS

Update all drivers

Update firmware on all 3 monitors

Open PC for cleaning and to confirm good connection for all cables and components

Confim that all DP wires are working and compatible

Confim that all DP ports on monitors and GPU are working and compatible

Yes, I have selected "extend display"

Lower resolution and refresh rates on each display (I went all the way down to 1080p, 60hz)

Tried using HDMI on one monitor and got the same result with the HDMI connected monitor

I have made each display the third monitor and got the same result with the new third monitor

Connect each monitor one at a time

Disabled Intel HDU graphics (read that idea on a forum)

Disabled G-Sync

Plugged each power adapter in to their own wall outlet (to eliminate power strip issues)

Downloaded some NVIDIA DisplayID driver (I have no idea what it is but I'm desparate)

Tried the Surround feature on Geforce Control Panel

Disconnected all other peripherals from PC

Specs:

Monitors- Samsung G80SD x3 (up to 4K 240Hz)

OS- Windows 11 licensed

GPU- EVGA RTX 3090ti FTW3 24GB (not overclocked)

Motherboard- MSI MPG Z690 Carbon

CPU - 12 Gen Intel i9 12900K 3.20 GHz (not overclocked)

RAM - Corsair 32GB (16 x 2) DDR5

PSU - EVGA 850w

Displayport Cable - supplied with the monitors (I believe 1.4)

All components were purchased brand new and are from a reputable brand (no TEMU stuff)

Make sure all your dp cables are vesa certified. Just because it came with the monitor doesn't mean they are vesa certified cables.