i use ubuntu studio 7.04, and my monitor is philiph 105G7.video card is Nvidia 6300XT.but i can't get resolution on 1024X768.I use Two Hard Drive.The first one is for Windows, And the 2nd one is for linux ubuntu studio,Windows is set to 1024X768.but the highest screen resolution on ubuntu only 800X640

First back up xork.conf:
OPen a terminal and type "sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.bak".
Then edit xorg.conf
Type "gksudo gedit /etc/X11/xorg.conf". Scroll down to the Section "Monitor" and put in the correct horizontal and vertical resolutions. Get them from your monitor's manual or google.
Then go down to Section "Screen" and under each section put your correct resolution (eg "1280x1024) in front of the resolutions listed there so that is the first one in each section. Save the file and reboot.
If that doesn't work hit ctrl+alt+F2, login and type
"sudo /etc/init.d/gdm stop" (this stops X) then:
"sudo dpkg-reconfigure xserver-xorg". Go through this and answer defaults to all. put in your horizontal and vertical resolutions and again and select the display resolutions with the space bar when it asks. When finnished reboot and you should be good. If you had the nvidia driver installed you will need to reinstall if after reconfiguring X.

thanks tommcd..i'll try it