LinuxQuestions.org - CPU Overheating in TOSHIBA M-500 please help

From experience I can tell you that the fix for this is hardware, not software. Laptops accumulate dust in the radiator (finned portion) of the heatpipe heatsink, and the fans get enough fine dust on the motor shaft to slow them down. The solution is to disassemble the laptop enough to either remove the heatsink and clean it, then replace it with new thermal paste, or just clean it in situ with compressed air. The fans are generally easier to remove, and many have a cover that can be removed that will allow the fan blades to be pulled out. This exposes the motor shaft. Get some sewing machine oil (very fine oil -- not 3-in-1 oil, it's vegetable based) and wipe the shaft clean. Apply a little oil, reinsert the fan blade motor shaft and spin it, then remove again, wipe clean again and reoil. Repeat a few times to wash all the dirt out of the shaft and bearing, then oil lightly and reassemble.