Ubuntu 修改分辨率为1024x768 24位

（1）修改grub文件:
sudo vim /etc/default/grub
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# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.

GRUB_DEFAULT=0
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`

#need to add this line####################################################
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset video=uvesafb:mode_option=1024x768-24,mtrr=3,scroll=ywrap"
#add end #############################################################

GRUB_CMDLINE_LINUX=""

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# 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=1280x800

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_LINUX_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"
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（2）修改initramfs:

sudo gedit /etc/initramfs-tools/modules

-------------------------------------------------------------------------------------------------------------------
# List of modules that you want to include in your initramfs.
#
# Syntax: module_name [args ...]
#
# You must run update-initramfs(8) to effect this change.
#
# Examples:
#
# raid1

# sd_mod

#need to add this line###########################

uvesafb mode_option=1024x768-24 mtrr=3 scroll=ywrap

#add end############################ ########
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（3）强制使用Framebuffer:

echo FRAMEBUFFER=y | sudo tee /etc/initramfs-tools/conf.d/splash

（4）更新grub和initramfs:
sudo update-grub2

sudo update-initramfs -u

（5）重启