I have used the subject machine at least a hundred times with a projector that handles only 1024x768 (the 'native' resolution of the system is 1400x1050).

On the first use I had to set the resolution to 1024x768 on my system in order to get the display on the projector.
EVERY TIME after that first time, whenever I attached the projector to the system the resolution would AUTOMATICALLY adjust itself to 1024x768 and when I disconnected it sometimes reverted automatically to native resolution and sometimes I had to do it manually.

However, all those time the resolution at 1024x768 would show on the system display itself as a FULL SCREEN.

Suddenly one day, in the middle of a presentation using the projector, the system screen shrunk, apparently to a REAL 1024x768 (versus the interpolated (I assume) display of previously which filled the full screen).
This 'real' 1024x768 only occupies about 5/8ths of the screen.

This also happens whenever I change the resolution to 1024x768 manually, even without the projector attached.

This is a real PITA and I sure hope someone can tell me how to get things back the way they were.

Thanks for any help on this

Jim