Re: "[mi] EQ overflowing. The server is probably stuck in an infinite loop."
I ran into this issue as well, using openSUSE 11.3 x86_64. I solved the problem by upgrading the kernel to Linux 2.6.36-93-default x86_64. After the kernel update, ALL lockup issues and heavy xorg cpu usage issues were solved.
Nvidia GTX 260
Compositing via KWIN
NVIDIA Driver Version 260.19.21