Dual display issues, screensaver crashes, and plain ol' quirks with a 2nd display

My system setup is this:
20" imac
4GB RAM
22" HP w2207 LCD monitor (rotated vertically)
Firewire audio interface - FW400
WD Terabyte Firewire 800 drive

I have an HP w2207 monitor as the 2nd monitor for my imac. The ATI Radeon video card is supposed to be able to handle two monitors, but that doesn't mean it's seamless. It struggles a lot and I'm sure that fact isn't publicized about some of the video weakness in the new aluminum imacs, except for the one graphics update that erroneously downplayed the problem as applying only to avid gamers and video hogs. I did neither and had serious probs before that. And then the update was renamed completely with references to video problems stripped out. Hmm?

I've noticed the following quirks:

1. When I had the infamous crashing imac before mac replaced it and gave me a later batch model, a lot of crashes were caused by or related to the unit going to sleep and not being able to wake up with 2 monitors attached. If I turned the extra monitor off before letting the system sleep, less crashes. Hmmm.
2. Something about how the imac handles Firewire somehow interferes with the video display. I had a firewire audio interface, that even when it wasn't actively demanding system resources, it causes the video display to flash erratically. This is the only thing I'm mentioning, but not the only problem I've noticed where Firewire takes something else unrelated down with it. I've since bought a different Firewire interface, but among the 3 I've used, there are some consistencies. I've since DOWNGRADED not only from Leopard back to Tiger (which ran like a charm) but I've downgraded my version of Firewire implementation. Apple wrote a patch for Tascam that took the Firewire implementation back to the way it was done in 10.4.9 which was super stable. If that's not an admission of something, I don't know what is.
3. When I reboot and the 2nd monitor is already on, my mac will hang on the blue start up screen, sometimes indefinitely (today I walked my dog and came back and it hadn't progressed at all) until I flick the power for the 2nd display on and off and then voila! The mac osx progress bar comes on the screen and it tries to redraw the desktop wallpaper, etc. So it works, but I actually SEE it struggle with the 2nd monitor on. If I were to do this whole startup b4 turning on the monitor, it goes much quicker and you don't see the redrawing of the screen with the temporary blue screen while it's thinking. Meaning, the progress bar comes up, it flash back blue on both screens for 1 second or 2, then it brings up the wallpapers.
4. Even with the new Firewire audio interface, my system wigs out if I have the screensaver on both screens. I got some crashes until I told it to just turn the 2nd screen black and only do the moving screensaver on the 1st screen.

So there you have it. If this helps anyone with similar issues, I'm happy to share it.

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