If you can change to a tty (ctrl alt F1) then login and use
xrandr -q 'this will display a list of modes with the connected device for you to choose'
set the one you want with
xrandr --output LVDS --mode 1920x1080
For example, make sure you use the correct display identifier given by
xrandr -q, mine being LVDS.
You can see which from the output of xrandr -q
for example mine is
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 1920 x 1920
LVDS connected 1920x1080+0+0 (normal left inverted right x axis y axis)
Then when set, switch back to your desktop with ctrl alt F7 (possibly F8 if F7 doesnt do it)