I recently got some additional monitors and have been trying to span my desktop across them. My GTX1060 can only drive 4 monitors at a time so I have added an older GTX660 to my system as well since the both use the same Nvidia driver. My OS is currently Ubuntu MATE 17.10 on kernel 4.13.
All the Monitors I have connected show up in the nvidia-settings app but I cannot set them all to be a part of the same X screen the way I had with 3 monitors. The options I have found are to have tried are one X screen for each GPU and one X screen for each monitor. Enabling Xinerama has not worked for me at all, some monitors do not turn on at all and the rest repeatedly turn on and off; in this case I cannot even switch to tty1 to reset my xorg.conf. In the non Xinerama configurations all the monitors turn on and I can move the cursor to them, but on screens other than Xscreen0 the desktop background is not rendered and opening a window will cause all window decorations to disappear. In the ARandR config tool for XRandR, only monitors connected to GPU0 appear. Additionally, When I have multiple X screens active, windows will try to fullscreen across multiple monitors and into dead space; this is why I initially tried setting every monitor to its own Xscreen.
How can I configure my my system to let me use all monitors, but also let me fullscreen windows to one monitor at a time? If possible I would like to avoid Xinerama so that I can keep graphical acceleration.
XRandR does not see Second GPU
~$ xrandr --listproviders
Providers: number : 1
Provider 0: id: 0x1b9 cap: 0x1, Source Output crtcs: 4 outputs: 8 associated providers: 0 name:NVIDIA-0
~$ xrandr
Screen 0: minimum 8 x 8, current 6280 x 1600, maximum 32767 x 32767
DVI-D-0 connected primary 2560x1440+900+0 (normal left inverted right x axis y axis) 597mm x 336mm
2560x1440 59.95*+
HDMI-0 connected 900x1600+5380+0 left (normal left inverted right x axis y axis) 443mm x 249mm
1600x900 60.00*+
1280x800 59.81
1280x720 60.00
1152x864 75.00
1024x768 75.03 70.07 60.00
800x600 75.00 72.19 60.32 56.25
640x480 75.00 72.81 59.94
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 connected 900x1440+0+0 right (normal left inverted right x axis y axis) 408mm x 255mm
1440x900 59.89*+
1280x1024 75.02 60.02
1280x960 60.00
1152x720 60.00
1024x768 75.03 60.00
800x600 75.00 60.32
640x480 75.00 59.94
DP-2 connected 1920x1200+3460+0 (normal left inverted right x axis y axis) 518mm x 324mm
1920x1200 59.95*+
1920x1080 60.00
1680x1050 59.95
1600x1200 60.00
1280x1024 60.02
1280x960 60.00
1024x768 60.00
800x600 60.32
640x480 59.94
DP-3 disconnected (normal left inverted right x axis y axis)
DP-4 disconnected (normal left inverted right x axis y axis)
DP-5 disconnected (normal left inverted right x axis y axis)
Nvidia driver does see second GPU
~$ nvidia-xconfig --query-gpu-info
Number of GPUs: 2
GPU #0:
Name : GeForce GTX 1060 6GB
UUID : GPU-7cf9de5d-f214-1a28-a5ca-70d2a261e96f
PCI BusID : PCI:1:0:0
Number of Display Devices: 4
Display Device 0 (TV-0):
EDID Name : CRO 27QHD
Minimum HorizSync : 88.787 kHz
Maximum HorizSync : 88.787 kHz
Minimum VertRefresh : 59 Hz
Maximum VertRefresh : 59 Hz
Maximum PixelClock : 241.500 MHz
Maximum Width : 2560 pixels
Maximum Height : 1440 pixels
Preferred Width : 2560 pixels
Preferred Height : 1440 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 600 mm
Physical Height : 340 mm
Display Device 1 (TV-1):
EDID Name : Acer S201HL
Minimum HorizSync : 30.000 kHz
Maximum HorizSync : 80.000 kHz
Minimum VertRefresh : 50 Hz
Maximum VertRefresh : 76 Hz
Maximum PixelClock : 160.000 MHz
Maximum Width : 1600 pixels
Maximum Height : 900 pixels
Preferred Width : 1600 pixels
Preferred Height : 900 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 440 mm
Physical Height : 250 mm
Display Device 2 (TV-3):
EDID Name : HP w1907
Minimum HorizSync : 24.000 kHz
Maximum HorizSync : 83.000 kHz
Minimum VertRefresh : 50 Hz
Maximum VertRefresh : 76 Hz
Maximum PixelClock : 140.000 MHz
Maximum Width : 1280 pixels
Maximum Height : 1024 pixels
Preferred Width : 1440 pixels
Preferred Height : 900 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 410 mm
Physical Height : 260 mm
Display Device 3 (TV-4):
EDID Name : DELL U2412M
Minimum HorizSync : 30.000 kHz
Maximum HorizSync : 83.000 kHz
Minimum VertRefresh : 50 Hz
Maximum VertRefresh : 61 Hz
Maximum PixelClock : 170.000 MHz
Maximum Width : 1920 pixels
Maximum Height : 1200 pixels
Preferred Width : 1920 pixels
Preferred Height : 1200 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 520 mm
Physical Height : 320 mm
GPU #1:
Name : GeForce GTX 660
UUID : GPU-2836f016-3ecd-fb99-63bc-457cfb8abf6f
PCI BusID : PCI:3:0:0
Number of Display Devices: 2
Display Device 0 (TV-0):
EDID Name : DELL 1708FP
Minimum HorizSync : 30.000 kHz
Maximum HorizSync : 81.000 kHz
Minimum VertRefresh : 56 Hz
Maximum VertRefresh : 76 Hz
Maximum PixelClock : 140.000 MHz
Maximum Width : 1280 pixels
Maximum Height : 1024 pixels
Preferred Width : 1280 pixels
Preferred Height : 1024 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 340 mm
Physical Height : 270 mm
Display Device 1 (TV-3):
EDID Name : DELL 1708FP
Minimum HorizSync : 30.000 kHz
Maximum HorizSync : 81.000 kHz
Minimum VertRefresh : 56 Hz
Maximum VertRefresh : 76 Hz
Maximum PixelClock : 140.000 MHz
Maximum Width : 1280 pixels
Maximum Height : 1024 pixels
Preferred Width : 1280 pixels
Preferred Height : 1024 pixels
Preferred VertRefresh : 60 Hz
Physical Width : 340 mm
Physical Height : 270 mm