I have An ATI X850 and it has a VGA and a DVI on the back, On windows i was able to extend my desktop onto my LCD TV.

Right now i have both screens on, but its the same image, I want to know how to extend the desktop.

Any help is appreciated, Thanks.

Sounds like 'clone' is being used. Try using the fglrx config tool to see if you can turn off clone, or take a look at your xorg.conf and see if it is set there.

Thanks, But i have literally just installed linux so i have no idea what i would be looking for or what to do.

So you just plugged in the TV and magically worked? Well how about that!

Now it is just a matter of getting the display properties correct. Which flavor of Linux are you using, Ubuntu, Suse, Fedora? And what desktop, Gnome, KDE?

There should be config menu somewhere were you can adjust the display, but it shifts location and name based on what flavor of Linux you are using.

Yeah i plugged the TV into the DVI and it had to install ati drivers and restart, after that it was just cloned.

Im using Ubuntu 8.04 and Gnome.

Here are few links I found that might help;
http://ubuntuforums.org/showthread.php?t=85215
http://ubuntuforums.org/showthread.php?t=221174

Looks like you need to run "sudo aticonfig" to reconfigure your display settings.

Since you are new to Linux you probably don't know about bash completion. When you open a terminal it is using the Bash shell, which in most Linux distros has an extra option installed to enable autocompleation by pressing 'tab' key twice. I mention since since I think the proprietary 3d driver from ATI is called 'fglrx' and the commands it uses to configure things beings with that name. So by typing 'fglrTABTAB' and pressing tab key twice, will give you list of possible commands that begin with these letters.

Now it should be easier for you to find commands, or the correct spellings if you can only remember the fist few letters.