I cant see how to change the resolution of the screen, there is no way to change something in the settings.
maybe something wrong with my monitor? (LG Flatron W2452T)
to make my situation more worse, zero experience with Linux
I tried the linked instructions and pasted the lines into my /etc/rc.local script
It did not help. I still got 1920 x 1080 output when hooked up to my 1280 x 800 monitor and after a few seconds the screen was a mess. This messed up screen also showed up after a few seconds when connected to a 1920 x 1080 display.
I deleted the lines and the screen is once again stable (still no 1280 x 760 support)
Setting the /etc/rc.local gives me a clean 1080p Ubuntu display:
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "" on success or any other
# value on error.
# In order to enable or disable this script just change the execution
# By default this script does nothing.
echo 1080p60hz > /sys/class/display/mode
fbset -fb /dev/fb0 -g 1920 1080 1920 1080 24
fbset -fb /dev/fb1 -g 32 32 32 32 32
echo 0 > /sys/class/graphics/fb0/free_scale
echo 1 > /sys/class/graphics/fb0/freescale_mode
echo 0 0 1919 1079 > /sys/class/graphics/fb0/free_scale_axis
echo 0 0 1919 1079 > /sys/class/graphics/fb0/window_axis
echo 0 > /sys/class/graphics/fb1/free_scale
echo 0 > /sys/class/graphics/fb0/blank
echo breathe > /sys/class/leds/red/trigger