On Mon, 06 May 2019 14:13:03 -0700, skybuck2000 wrote:

How does the GT 520 auto-detect the connected the device ?

It has 3 connectors: VGA, HDMI and DVI.

What I want to do is:

1. Use VGA always for monitor.
2. Use HDMI only for audio connection to receiver.

Problem with this setup is that GT 520 believes receiver to be a monitor
and switches to it automatically on boot, with different/weird results,
either no screen, or bad screen.

....snip...


The "manual override" is to specify what port is to be used for which X
screen. This is "easy" with the proprietary nvidia blob, might be more
difficult is you are using nouveau or nv. For example, I have a 4K
monitor on a GTX1060 and 2 1080p monitors on a GTX660 (both on same linux
box). I use the "metamode" option to specify the output. For example:

Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "Stereo" "0"
Option "nvidiaXineramaInfoOrder" "DFP-6"
Option "metamodes" "3840x2160_60 +0+0
{AllowGSYNCCompatible=On}; nvidia-auto-select +0+0"
Option "SLI" "Off"
Option "MultiGPU" "Off"
Option "BaseMosaic" "off"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Screen"
Identifier "Screen1"
Device "Device1"
Monitor "Monitor1"
DefaultDepth 24
Option "Stereo" "0"
Option "metamodes" "DVI-I-1: 1920x1080_60 +0+0
{AllowGSYNC=Off}; DVI-I-1: nvidia-auto-select +0+0"
Option "SLI" "Off"
Option "MultiGPU" "Off"
Option "BaseMosaic" "off"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Screen"
Identifier "Screen2"
Device "Device2"
Monitor "Monitor2"
DefaultDepth 24
Option "Stereo" "0"
Option "metamodes" "DVI-D-0: 1920x1080_60 +0+0
{AllowGSYNC=Off}"
Option "SLI" "Off"
Option "MultiGPU" "Off"
Option "BaseMosaic" "off"
SubSection "Display"
Depth 24
EndSubSection
EndSection