How to make 2 monitors friends in Ubuntu 18?

Question

NVIDIA

There are 2 Nvidia GeForce GTX 1050TI and GTX 650 video cards. A monitor is connected to each (in 1050TI there is simply no VGA input ....). It seems that everything was set up correctly in the Nvidia x server, but on the second screen, when transferred to it, the cursor displays the cursor in the form of an "X" on an eternally black background. It is necessary to expand the screens (end of the first, continuation of the second). What to do?

Answer 1

man X
man xrandr The
truth will still look clumsy and can fall corny - at least I didn't like the word at all. There was a somewhat similar situation - an integra and nvidia, HDMI on an integra drove not like a child, I thought to get out through the X config, I googled a lot. As a result, it turned out that:
- two monitors and two video cards are described in xorg.conf

Section "Monitor"
    Identifier  "NEC MultiSync LCD2690WUXi"
    VendorName  "NEC"
    ModelName   "MultiSync LCD2690WUXi"
    HorizSync   32 - 92
    VertRefresh 50 - 85
     Option "DPMS"
    Option "PreferredMode" "1920x1200"
EndSection
Section "Monitor"
    Identifier  "AOC I2475PQRU"
    VendorName  "AOC"
    ModelName   "I2475PQRU"
    HorizSync   15 - 83
    VertRefresh 50 - 76
     Option "DPMS"
EndSection
Section "Device"
    Identifier  "Intel HD 4000 integrated card"
    Driver      "intel"
    Option      "Monitor-VGA1"  "AOC I2475PQRU"
    BusID       "PCI:0:2:0"
    Option      "NoAccel"       "False"
    Option      "DRI"           "True"
    Option      "AccelMethod"   "sna"
EndSection
Section "Device"
    Identifier  "NVidia GeForce GTS 250"
    Driver      "nouveau"
    Option      "Monitor-DVI-I-1" "NEC MultiSync LCD2690WUXi"
    VendorName  "NVidia"
    BoardName   "GeForce GTS 250"
    BusID       "PCI:1:0:0"
    Option      "NoLogo" "YES"
EndSection

- each monitor is tied to its own video card
- monitors and video cards are linked in the Screen section - there are two sections

Section "Screen"
    Identifier  "Screen 1"
    Device      "NVidia GeForce GTS 250"
    Monitor     "NEC MultiSync LCD2690WUXi"
    DefaultDepth 24

    Subsection "Display"
        Depth       24
        ViewPort    0 0
        Modes "1920x1200"
    EndSubsection
EndSection
Section "Screen"
    Identifier  "Screen 2"
    Device      "Intel HD 4000 integrated card"
    Monitor    "AOC I2475PQRU"
    DefaultDepth 24

    Subsection "Display"
        Depth       24
        ViewPort    0 0
       Modes "1920x1200"
    EndSubsection
EndSection

- both screens are described in the Layout section and Xinerama is included

Section "ServerLayout"
  Identifier "Sentry Layout"
  Screen 0 "Screen 1"
  Screen 1 "Screen 2" RightOf "Screen 1"
  Option "Xinerama" "1"
EndSection

Works badly. Find a better adapter :)