log-in screen resolution problem with ubuntu 8.04

i'm having a problem with the resolution on my log-in screen the following is my xorg.conf
pls help
# 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.
#
# 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 "InputDevice"
 Identifier "Generic Keyboard"
 Driver "kbd"
 Option "XkbRules" "xorg"
 Option "XkbModel" "pc104"
 Option "XkbLayout" "us"
EndSection

Section "InputDevice"
 Identifier "Configured Mouse"
 Driver "mouse"
 Option "CorePointer"
EndSection

Section "Device"
 Identifier "Configured Video Device"
 Driver "nvidia"
 Option "NoLogo" "True"
 Option "UseEdidFreqs" "True"
 Option "AllowGLXWithComposite" "True"
EndSection

Section "Monitor"
 Identifier "Configured Monitor"
 HorizSync 30-96
 VertRefresh 50-160
 modeline "800×600@56" 36.0 800 824 896 1024 600 601 603 625
 modeline "800×600@72" 50.0 800 856 976 1040 600 637 643 666
 modeline "800×600@75" 49.5 800 816 896 1056 600 601 604 625
 modeline "800×600@60" 40.0 800 840 968 1056 600 601 605 628
 Modeline "1024×768@60" 64.56 1024 1056 1296 1328 768 783 791 807
 Modeline "1152×720@60" 66.75 1152 1184 1432 1464 720 735 742 757
 modeline "1152×768@54" 64.995 1152 1178 1314 1472 768 771 777 806
 Modeline "1280×800@60" 83.91 1280 1312 1624 1656 800 816 824 841
 modeline "1280×854" 80.0 1280 1309 1460 1636 854 857 864 896
 modeline "1280×768@60" 80.14 1280 1344 1480 1680 768 769 772 795
 modeline "1280×720@60" 74.48 1280 1336 1472 1664 720 721 724 746
 modeline "1280×800@75" 107.21 1280 1360 1496 1712 800 801 804 835
 modeline "1280×768@75" 102.98 1280 1360 1496 1712 768 769 772 802
 modeline "1280×720@50" 60.47 1280 1328 1456 1632 720 721 724 741
 modeline "1280×800@60" 83.46 1280 1344 1480 1680 800 801 804 828
 modeline "1440×900@75" 136.49 1440 1536 1688 1936 900 901 904 940
 modeline "1440×900@60" 106.47 1440 1520 1672 1904 900 901 904 932
 modeline "1600×1024@60" 136.36 1600 1704 1872 2144 1024 1025 1028 1060
 modeline "1680×1050@60" 147.14 1680 1784 1968 2256 1050 1051 1054 1087
 modeline "1680×1050@75" 188.07 1680 1800 1984 2288 1050 1051 1054 1096
 modeline "1920×1200@60" 193.16 1920 2048 2256 2592 1200 1201 1204 1242

EndSection

Section "Screen"
 Identifier "Default Screen"
 Monitor "Configured Monitor"
 Device "Configured Video Device"
 Defaultdepth 24
 SubSection "Display"
 Depth 24
 Modes "1440×900@60" "1600×1024@60" "1440×900@75" "1680×1050@60" "1280×800@60" "1680×1050@75" "1280×720@50" "1920×1200@60" "1280×768@75" "1280×800@75" "1280×720@60" "1280×768@60" "1280×800@60" "1280×854" "1152×720@60" "1152×768@54" "1024×768@60" "800×600@60" "800×600@75" "800×600@72" "800×600@56"
 EndSubSection
EndSection

Section "ServerLayout"
 Identifier "Default Layout"
  screen "Default Screen"
EndSection
Section "Module"
 Load "glx"
EndSection