Broken screen! Please help!
I have an older style iMac. The screen is starting to go on it. I turn it on and I can see half of the screen fine, the other half has a thick white line or box down the middle of it. I have an external monitor that I hooked up to it using the DVI connection. However, now when I turn it on, it looks like it's a dual connection so I just get a bigger screen now. I'd like for the external monitor just to be the desktop (mirror the iMac) and use only that monitor as the main screen. How can I do this so that's it not a dual screen and it's just a mirror image?!