I have Lubuntu 18.04 LTS installed on a machine that has a discrete graphics card with DVI and displayport as well as on board connections for 2x HDMI and a displayport. I have a total of 3 monitors with one rotated 90 degrees and connected via DVI on the discrete graphics card and the remaining two monitors connected to the on board 2x HDMI ports. Below is the graphics hardware information for my configuration:
sudo lshw -C display [sudo] password for username: *-display description: VGA compatible controller product: Oland [Radeon HD 8570 / R7 240/340 OEM] vendor: Advanced Micro Devices, Inc. [AMD/ATI] physical id: 0 bus info: pci@0000:01:00.0 version: 00 width: 64 bits clock: 33MHz capabilities: pm pciexpress msi vga_controller bus_master cap_list rom configuration: driver=radeon latency=0 resources: irq:30 memory:c0000000-cfffffff memory:d0000000-d003ffff ioport:e000(size=256) memory:d0040000-d005ffff *-display description: VGA compatible controller product: Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 06 width: 64 bits clock: 33MHz capabilities: msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:29 memory:d0400000-d07fffff memory:b0000000-bfffffff ioport:f000(size=64) memory:c0000-dffff
All three monitors are configured with xrandr/arandr GUI program with the following configuration at startup in Lubuntu 18.04 LTS via a desktop file (lxrandr-autostart.desktop) in /home/username/.config/autostart/:
[Desktop Entry] Type=Application Name=LXRandR autostart Comment=Start xrandr with settings done in LXRandR Exec=/home/username/.screenlayout/triple-monitor-layout-portrait.sh OnlyShowIn=LXDE
The contents of triple-monitor-layout-portrait.sh is as follows:
#!/bin/sh xrandr --output VGA-1 --off --output DisplayPort-1-2 --off --output DVI-1-0 --mode 1600x900 --pos 3840x0 --rotate left --output HDMI-2 --mode 1920x1080 --pos 0x248 --rotate normal --output HDMI-1 --primary --mode 1920x1080 --pos 1920x248 --rotate normal --output DP-2 --off --output DP-1 --off
At login for Lubuntu 18.04 LTS, I encounter a black screen for a few seconds on all three monitors after entering my password and am returned to the login screen. This usually occurs repeatedly until Lubuntu 18.04 LTS is successful in login. Also, upon login the monitor connected to DVI-1-0 sometimes displays a black screen that shows nothing except for my mouse if I move it onto the monitor. I usually have to logout/login several more times to get a picture to display properly on the DVI-1-0 monitor.
How do I configure xrandr so that I can login with all three monitors working as expected?