如果ubuntu内核改变之后显示分辨率发生变化，那么更改/etc/defaut/grub配置文件

sudo gedit /etc/default/grub

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
GRUB_GFXMODE=1920x1080
GRUB_GFXPAYLOAD_LINUX=1920x1080