Resolution Issue on karmic

begitu abis nginstall karmic ubuntu di komputer,,ternyata resolusinya maksimal 800×600 aj
jadi gede2 gt,,hkiz…
seingetku ini masalah di seting xservernya biasanya ada di file xorg.conf
langsung menuju tkp : /etc/X11/
tp sialnya ga ad satu file pun yg namanya xorg.conf
setelah baca2 forum dan eksperimen…sampai ga bs masuk gdm,,,hehe
aq bikin file xorg.conf baru dengan akses super user tentunya :
nah isinya :

# xorg.conf (X.Org 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 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.
#
# Note that some configuration settings that could be done previously
# in this file, now are automatically configured by the server and settings
# here are ignored.
#
# 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 “Monitor”
    Identifier    “Configured Monitor”
    HorizSync    20-50
    VertRefresh    40-90
EndSection

Section “Screen”
    Identifier    “Default Screen”
    Monitor        “Configured Monitor”
    Device        “Configured Video Device”
    SubSection “Display”
        Depth    1
        Modes    “1152×864” “1024×768” “832×624” “800×600” “720×400” “640×480” “640×350”
    EndSubSection
EndSection

Section “Device”
    Identifier    “Configured Video Device”
EndSection