Thanks for the help! I played around a bit today, and now I have a working GNOME desktop. Now I just need to switch to KDE... here's what I did today. On nVidia's website, they have a list of all the options that can be thrown into xorg.conf. Two of those deal with specifying monitor types. I used:
Option "Connected Monitor" "DFP"
to specify monitor type. I also noticed in my /var/log/Xorg.0.log that the nVidia driver was complaining about not being able to connect to the ACPI Event Daemon. I then installed it (acpid) by following Hlinger's instructions here
. This didn't solve my problem, but the nVidia driver did stop complaining about ACPI Events. Also, I'm in the process of turning this computer into a multiseat setup, so I have two graphics boards, monitors, etc. When I installed the OS, I had X automatically generate an xorg.conf. It recognized both graphics boards and monitors, but only generated one screen setup. Today I edited it to add in the extra screen. I then added the new screen to the ServerLayout section. My server layout now looks like:
Identifier "single head configuration"
Screen 0 "Screen0" 0 0
# I added Screen1-didn't touch anything else
Screen 1 "Screen1" 0 0
InputDevice "Mouse0" "CorePointer"
InputDevice "Keyboard0" "CoreKeyboard"
Option "DontZap" "false"
After this edit, when I run startx GNOME comes up just fine. ( I did install XFCE, but I had installed GNOME earlier. Not sure why the XFCE install didn't reconfigure the desktop started with startx.)
I have attached Xorg.0.log(I had to rename it to Xorg.0.log.txt) and xorg.conf,
Thank you very much to everyone who has helped me on this problem.