X600 driver instability?

Yo, Is anyone else seeing instability in recent X600 builds in Fedora (when using 3D desktop effects)? I'm getting occasional X server crashes that never used to happen with this driver - I haven't had chance to track down when it started happening in as of yet but the box stability is restored by disabling desktop effects. I need this box, but I'll schedule some crash time over the weekend or something. Next time it happens, I'll capture the X server output. There's no oops but a reproducer seems to be along the lines of: * Login to desktop * Restart VPN and connect to remove IRC proxy * xchat goes nuts with popups catching up replay traffic * kernel ringbuffer shows random segfaults from e.g. DBUS Not much to go on yet. Just thought I'd share :) Jon.