Can't find optimal screen resolution

Solution 1:

Try first to define a VIRTUAL1 display:

xrandr --newmode "1440x900_60.00" 106.47 1440 1520 1672 1904 900 901 904 932 -HSync +Vsync

And use it to set the profile of VGA-1:

xrandr --addmode VGA-1 1440x900_60.00