Re: geforce 6600 random system lock
The "irq nobody cared" message typically suggests a BIOS bug.
According to your bug report, the glx module failed to load, which suggests to me that the NVIDIA driver isn't correctly installed.
Have you verified that you're using the latest BIOS for the motherboard?
Have you tested with NvAGP set to 0 in xorg.conf ?
Does this problem also reproduce with the 1.0-9625 beta driver?