I am contemplating going to a dual monitor setup. What video cards are out there that will allow this and which of these seems to work the best. Also what if any adjustments need to be made to Photoshop ( CS ) to work in a dual monitor setup ? thanks for the help

Most of the geoforce 4 cards will drive 2 monitors just check the specs for the monitor connectors. I didnt have to make any software changes to Photoshop just have the workspace on your best/biggest monitor and drag all the tools, palettes etc onto the other.

The ATI radeon 9600, 9700 and 9800 Pro series do a remarkable job with dual monitor displays. They also enable you to set multipule color profiles and do some very fine tuning on the monitor calibration side of things.
The other advantage they have over the Nvida Gforce series (even the newest ones) is that they have more power and seem to offer better stability. I have the 9800 Pro and I'd swap my granny before I'd give up this card. :D

Ultimately, it will come down to a matter of preference. As Chris H said, "check the specs."

** Paris **