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noctlos

Member

Registered: 2013-08-26

Posts: 36

[Solved] using monitors with separate graphics cards

I have an nVidia card and an ATI card. I have one monitor plugged into each. After much trouble, I have finally gotten them both to be on at the same time when I start my display manager (gdm). The nVidia card is the primary one that my BIOS gives video to when I boot. Now, when I start GDM, the nVidia (Left) screen shows the display manager, and the ATI (Right) screen is black, but I can move my mouse between the two. Upon starting my X session (Gnome, GDM), xrandr only shows the Left screen. I cannot drag windows to the Right screen. When my mouse enters the right screen, the cursor is the 'X' cursor.

Here's my /etc/X11/xorg.conf that got the right screen to turn on in the first place:

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0"
    Screen      1  "Screen1" RightOf "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Monitor"
    Identifier     "Monitor1"
    Option         "primary" "true"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
EndSection

Section "Device"
	Identifier 	"Device1"
	Driver		"radeon"
	BusID		"PCI:2:0"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen1"
    Device         "Device1"
    Monitor        "Monitor1"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

How do I get xrandr to recognize my second graphics card, and any displays that are attached to it?
Currently it shows the following:

$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x2d9 cap: 0x1, Source Output crtcs: 4 outputs: 6 associated providers: 0 name:NVIDIA-0

Last edited by noctlos (2015-03-16 14:09:54)

noctlos

Member

Registered: 2013-08-26

Posts: 36

Re: [Solved] using monitors with separate graphics cards

I changed the nvidia drivers out for nouveau, and now xrandr sees both cards:

$ xrandr --listproviders
Providers: number : 2
Provider 0: id: 0xa8 cap: 0x7, Source Output, Sink Output, Source Offload crtcs: 4 outputs: 3 associated providers: 0 name:nouveau
Provider 1: id: 0x56 cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 4 outputs: 3 associated providers: 0 name:radeon

However, xrandr -q doesn't list any screens for my second card.

I have tried removing the xorg.conf file, in which case nothing comes up on the second screen.  With it there, I still get the black screen that a mouse can move around in, but applications won't open there.

Someone out there has to have some knowledge on this. Help?

After removing the xorg.conf file that I created (again), I run the following:

$ xrandr --setprovideroutputsource radeon nouveau 

After this, I can turn on my secondary display with no problems.

However, this is only for the nouveau driver. When I had the nvidia driver installed, it freaked out if the radeon module was loaded at all without the xorg.conf file. Because I intend to use the nvidia card for KVM VGA passthrough, I do need to have the nvidia driver instead of the nouveau on that card [or do i?]. Nevertheless, I suppose I can mark this thread as solved.

Last edited by noctlos (2015-03-16 14:09:45)