Nvidia virtual displays

Good afternoon!
I need help with my problem. Maybe somebody can help me with it. I use pc with nvidia p2220 with 4 DP out with xubuntu 20.04 lts. I need to run several virtual displays that i can use in my main layout with connected monitors. As we know, for 4 physical out in system we see 8 name alias like a DP-0, DP-1 etc. I connect physical monitor that use DP-7. Virtual monitor I can create only with ConnectedMonitor option in section screen. But! I can to use only name from DP-0 to DP-7 (8 alias total). But i don’t know that alias will be used next if I connect second physical display. And it can be an error. Please help, Can I use virtual displays with some others name like NDI-0 etc? Or maybe CRT or HDMI can help me. Because no hdmi or crt out on this card.
By the way, this problem I have because i need to connect ndi decoder to pc as physical display. It is have edid to and theoretical It is possible.
Hope you will help me with it.
With best regards

AFAIK, there’s no way to rename or add virtual connectors.
The gpu has 4 heads, 4 DP connectors which are dual-mode, i.e. DP/HDMI (over adapter). That’s why 8 connectors are displayed in the xorg logs, e.g. DP-0 is the displayport part of physical connector 0, DP-1 the HDMI part of it.

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Thank you for your reply! Don’t know about naming for DP and HDMI connector. As I understand I can use in this case 4 alias for virtual. 4 others for real DP connector. But how to detect what to dp and what for hdmi?

The Xorg logs tell about the connectors
(–) NVIDIA(GPU-2): DFP-0: Internal TMDS
TMDS is the protocol for HDMI/DVI

(–) NVIDIA(GPU-2): DFP-1: Internal DisplayPort
DisplayPort is obvious.

or run xrandr --verbose
will display:
SignalFormat: DisplayPort
SignalFormat: TMDS

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Also, please see this:

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Check it now
DP-5 connected 3840x2160+3840+0 (0x2a3) normal (normal left inverted right x axis y axis) 0mm x 0mm
Identifier: 0x298
Timestamp: 20478
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 1.0
CRTCs: 0 1 2 3
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
CTM: 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0
0 1
CscMatrix: 65536 0 0 0 0 65536 0 0 0 0 65536 0
BorderDimensions: 4
supported: 4
Border: 0 0 0 0
range: (0, 65535)
SignalFormat: TMDS
supported: TMDS
ConnectorType: DisplayPort
ConnectorNumber: 1
_ConnectorLocation: 1
non-desktop: 0
supported: 0, 1

As I understand
SignalFormat: TMDS
supported: TMDS
it means what it hdmi format. But it work now for DP physical connector.

It’s important what connector is used on the monitor side, seems to be HDMI.

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Thank you a lot! Now understand this logic.

You’ll have to distinguish between the physical connector type and the protocol delivered over it.
A physical DisplayPort connector on the gpu supports both DisplayPort and TMDS protocol
A physical HDMI connector on the gpu only supports TMDS protocol .

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