分辨率有问题，我的分辨率只有800＊600 和640＊480

[freeubuntu]

问题：打开系统－－>首选项－－>屏幕分辨率，以前用ubuntu6。06时分辨率有1024＊768 ，800＊600，640＊480三个选项，现在装了ubuntu7。04了，分辨率只有800＊600，640＊480两个选项了，我估计是显卡的问题，显卡是ATI radeon 9100,

我的显示设备如下：
显示设备:

显示卡 RADEON 9100 Family (Microsoft Corporation) (64 MB)

显示卡 RADEON 9100 Family (Microsoft Corporation) (64 MB)

3D 加速器 ATI Radeon 9100 (R200)

显示器 即插即用监视器 [NoDB] (WK7W073000666)

我的/etc/X11/xorg.conf 文件如下：
# /etc/X11/xorg.conf (xorg X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf(5) manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
# sudo dpkg-reconfigure -phigh xserver-xorg

Section "Files"
FontPath "/usr/share/fonts/X11/misc"
FontPath "/usr/share/fonts/X11/cyrillic"
FontPath "/usr/share/fonts/X11/100dpi/:unscaled"
FontPath "/usr/share/fonts/X11/75dpi/:unscaled"
FontPath "/usr/share/fonts/X11/Type1"
FontPath "/usr/share/fonts/X11/100dpi"
FontPath "/usr/share/fonts/X11/75dpi"
# path to defoma fonts
FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
EndSection

Section "Module"
Load "i2c"
Load "bitmap"
Load "ddc"
Load "dri"
Load "extmod"
Load "freetype"
Load "glx"
Load "int10"
Load "vbe"
EndSection

Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "CoreKeyboard"
Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
EndSection

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "CorePointer"
Option "Device" "/dev/input/mice"
Option "Protocol" "ImPS/2"
Option "ZAxisMapping" "4 5"
Option "Emulate3Buttons" "true"
EndSection

Section "InputDevice"
Driver "wacom"
Identifier "stylus"
Option "Device" "/dev/input/wacom"
Option "Type" "stylus"
Option "ForceDevice" "ISDV4" # Tablet PC ONLY
EndSection

Section "InputDevice"
Driver "wacom"
Identifier "eraser"
Option "Device" "/dev/input/wacom"
Option "Type" "eraser"
Option "ForceDevice" "ISDV4" # Tablet PC ONLY
EndSection

Section "InputDevice"
Driver "wacom"
Identifier "cursor"
Option "Device" "/dev/input/wacom"
Option "Type" "cursor"
Option "ForceDevice" "ISDV4" # Tablet PC ONLY
EndSection

Section "Device"
Identifier "ATI Technologies Inc Radeon R200 QM [Radeon 9100]"
Driver "ati"
BusID "PCI:2:0:0"
EndSection

Section "Monitor"
Identifier "770XC+"
Option "DPMS"
EndSection

Section "Screen"
Identifier "Default Screen"
Device "ATI Technologies Inc Radeon R200 QM [Radeon 9100]"
Monitor "770XC+"
DefaultDepth 24
SubSection "Display"
Depth 1
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1024x768" "800x600" "720x400" "640x480"
EndSubSection
EndSection

Section "ServerLayout"
Identifier "Default Layout"
Screen "Default Screen"
InputDevice "Generic Keyboard"
InputDevice "Configured Mouse"
InputDevice "stylus" "SendCoreEvents"
InputDevice "cursor" "SendCoreEvents"
InputDevice "eraser" "SendCoreEvents"
EndSection

Section "DRI"
Mode 0666
EndSection

[freeubuntu]

我认为是显卡导致分辨率不稳定。
看了http://forum.ubuntu.org.cn/viewtopic.php?t=26188
于是采取如下操作：
1）安装相关驱动
sudo apt-get update
sudo apt-get install linux-restricted-modules-$(uname -r)
sudo apt-get install xorg-driver-fglrx
sudo depmod -a
2）配置驱动
sudo dpkg-reconfigure xserver-xorg
sudo aticonfig --ovt=Xv
3）配置文件
sudo gedit /etc/X11/xorg.conf

添加一段 代码:
Section "Extensions"
Option "Composite" "0"
EndSection
4）重启xwindow，

结果xwindow无法启动。
请问如何解决这个问题呢？

[cashlu]

直接在xorg.conf里面把1024*768的分辨率手动加进去试试看