Well that went relatively painlessly. I just added an old HP 17inch LCD panel to my existing 28 inch ViewSonic. Both monitors are powered by a EVGA GeForce 8800GT. The Viewsonic is running at 1900×1200 and the HP at 1280×1024. Coupled with Spaces with 6 workspaces, I have effectively 12 monitors!! Woot!
The only reason I did this was because as I was trying to pick up some Xcode skills, I was finding it difficult to use the online web references and the Xcode development tool at the same time. Lots of Alt-Tabbing. Now I can keep the online reference in the second monitor and use the big screen for my main work area in Xcode.
I’m running 10.5.2 (although 10.5.3 is just out) – fully patched. The OS found both monitors without any issues and I was able to control them independently from System Preferences without having to resort to 3rd-party software. I also had the ability to change the orientation of either monitor, which surprised me. Something I may take advantage of once I get my office remodeled.