I have been having issues with my 2008 white macbook. It is a core2duo 2.4 Ghz. Running 10.6.4. I have upgraded the HD to 500GB and memory to 6GB. I started having random lockups 5-6 mos ago. Kenrel panics telling me to reboot. "unlocking an unlocked mutex" I noticed hard disk corruption associated with these, that I can repair with disk utility, but they recur with future panics. SMART reporting on the HD shows no problems, and I even checked the thorough report in ubuntu with no bad sectors or read/write errors. memtest86 runs all night with no troubles. Today while troubleshooting I noticed that my CPU temps are high. idle temps are in the mid 60s centigrade. When I run "yes > /dev/null" in two separte consoles, my temps spike to 105 C. I feel like this is a problem, and potentially the reason for my kernel panics. I am planning to dismantle the macbook and clean the fan, which my hardware monitor shows runs at 6200RPM max (which I believe is appropriate, but I bet it is dusty!). I have two questions: 1. Is this a probable cause of my problem? 2. Should I also reseat the heatsink while I am in there and put higher quality thermal compound like Arctic Silver on it? Thanks!