[PB2K]

Hi, I seem to have lost the ability to have a second screen next to my iMac screen

It's a 20" imac G5 2.1Ghz isight
the extra screen is a Samsung BW105 Syncmaster

both can display 1680x1050
I want to have a screen next to my iMac screen, no mirroring.

i reinstalled the system with original iMac install dvd's and still I don't see the "turn mirroring off" option in the display prefs. I also lost the "Arrange" tab. "detect displays' only results in the two screens showing the correct resolutions. They are both screen "1"

[ibook_steve]

What happens when you disconnect and reconnect the external display?

Steve

[Andhee]

try using an install disk if you got one with the monitor - only an idea.

[Cadaver]

Are you sure this version of the iMac can display a second desktop (extended) without the "extended desktop hack?"
You say "lost" in your post, so I assume you used to have it working, but verify that you didn't previously apply the hack. Same hack was required by the G3 and G4 iBooks.