I am using an ATI Radeon X1900 with Vista 64 bit. I am using ATI
Catalyst version 8.593.100.3. The problem is that when I try to extend
the display onto either a connected TV or a second monitor from within
the Catalyst Control Center nothing happens. I have tried a variety of
different resolutions including resolutions that are within the
capability of the second monitor but whenever I click on “Extend main
on to monitor” nothing happens. On the other hand cloning works just
fine, both on the TV in the second monitor.

Does anyone have any idea why this is happening and how to fix it
since I a major task over the next week that definitely requires
additional monitor screen area?

Thanks for any help in advance!