I have been struggling to find a solution to random system freezes of my Ubuntu box (Dapper). It all started since I installed nVidia drivers (I have a nVidia GeForce FX 5200 card) from Ubuntu repositories. Though I have followed all the steps specified in Ubuntu help forums, I couldn’t avoid annoying freezes until last night. The secret is the following addition under section “Devices” in /etc/X11/xorg.conf.
Option “NvAGP” “0″
"All that we are is the result of what we have thought. The mind is everything. "What we think we become."-Buddha