Como definir a resolução personalizada com xrandr e .xprofile?

Question

Estou tentando há dois dias definir a resolução nativa do meu monitor no xubuntu. Eu tive que instalar o kernel Linux 4.10 para ele iniciar o xfce. Eu executo esses comandos no meu perfil .x:

xrandr --newmode "1600x900_60.00"  118.25  1600 1696 1856 2112  900 903 908 934 -hsync +vsync
xrandr --addmode DP2 1600x900_60.00
xrandr --output DP2 --mode 1600x900_60.00

Mas no momento da inicialização, ele inicia o erro:

xrandr: Output DP1 is not disconnected but has no modes
xrandr: Output HDMI1 is not disconnected but has no modes
xrandr: Output HDMI2 is not disconnected but has no modes
xrandr: Output HDMI3 is not disconnected but has no modes
xrandr: Output DP1 is not disconnected but has no modes
xrandr: Output HDMI1 is not disconnected but has no modes
xrandr: Output HDMI2 is not disconnected but has no modes
xrandr: Output HDMI3 is not disconnected but has no modes
xrandr: Output DP1 is not disconnected but has no modes
xrandr: Output HDMI1 is not disconnected but has no modes
xrandr: Output HDMI2 is not disconnected but has no modes
xrandr: Output HDMI3 is not disconnected but has no modes

Qual eu acho que é um para cada comando no perfil .x. Adicionar este comando não ajuda nenhum dos dois.

xrandr --output HDMI1 --off --output HDMI2 --off --output HDMI3 --off --output DP1 --off

Programas como lxrandr ou arandr sempre acabam fazendo o xfce não inicializar e não me deixando fazer nada, nem mesmo mudar o tty.

Esta é minha saída xrandr:

eDP1 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00*+
   800x600       60.32    56.25  
   640x480       59.94  
   512x384       60.00  
DP1 disconnected (normal left inverted right x axis y axis)
DP2 connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00* 
   800x600       60.32    56.25  
   848x480       60.00  
   640x480       59.94  
HDMI1 disconnected (normal left inverted right x axis y axis)
HDMI2 disconnected (normal left inverted right x axis y axis)
HDMI3 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)

Meu hardware é:     - Asus H170 gaming pro     - Intel Core I7 7700     - Hyper X DDR4 8 Gb 2400 MHz

Obrigado por ler isto até agora.