如何修改centos 6.3 显示分辨率呢？
修改/etc/X11/xorg.conf的显示部分，在SubSection "Display" Depth 24 下加入一个行 Modes "1280x1024" "1024x768" "800x600"。
如果在/etc/X11目录下没有这个文件，可以用vi或者gedit创建一个，同样有效。
# VirtualBox generated configuration file
# based on /etc/X11/xorg.conf.
Section "Monitor"
Identifier "Monitor[0]"
ModelName "VirtualBox Virtual Output"
VendorName "Oracle Corporation"
EndSection
Section "Device"
BoardName "VirtualBox Graphics"
Driver "vboxvideo"
Identifier "Device[0]"
VendorName "Oracle Corporation"
EndSection
Section "Screen"
SubSection "Display"
Depth 24
Modes "1280x1024" "1024x768" "800x600"
EndSubSection
Device "Device[0]"
Identifier "Screen[0]"
Monitor "Monitor[0]"
EndSection