Regarding freezing, possible work around?
I just recently put together a new system (AMD X2 3800+ w/ 8600 GT card, fedora 7) and found myself having lockups as others have been describing here w/ 100.14.xx and/or 8600 cards and/or fedora 7. (i came the way while googling for possible solutions). Yes, I have RenderAccel, Composite, AIGLX, beryl, etc on (hey... eye candy is fun).
The surefire way for me to trigger it was go into screensaver settings, and preview and switch around between some screen savers. It would wedge X, leaving the mouse to work. Occasionally (very occasionally) it would recover. In every almost instance however I could go SSH into my box, switch init from 5 to 3 and back, and get a fresh login screen. (i think it stopped working one time after the ~10th time during a long run of trying to tweak it)
I think, I may have found a work around however. It's not perfect.. i still see occasional pauses (it seems to be certain workloads, IE: some screensavers are more likely/consistently causing it to happen, i can click to the next and it eventually notices). But it's not hiting the "point-of-no-return" I was seeing before.
Now, I added a couple of things just as i saw it fixed, i'll describe them all, but I *think* it might have been using:
Option "UseEvents" "True"
.. that did it... i saw a lot of 100% CPU spinning in either X, or beryl, or even BOTH when I was looking at the system as it hung, making it feel like some kind of communications breakdown... this seems to cause the driver to employ a different communications method, and so might be side-steping the issue.
I also added this one to enable the clocking features in the panel, as apparently the card I got comes out of the box overclocked, and I was going to try clocking it back to spec.
Option "Coolbits" "1"
This option has been a part of my other AIGLX box (an older XP 1800+ w/ GeForce 3), and has been very reliable (and speedy! much faster than even late model MacOSX systems effects), so i threw it in.
Option "TripleBuffer" "True"
These are the only other options set, both happened as the driver was activated via the livna install.
Option "AddARGBGLXVisuals" "True"
Option "DisableGLXRootClipping" "True"
I'd be interested in hearing if the switch to using events helps anyone else.