If I suspend the system and turn it back it on, the fan will properly kick in at high CPU temperatures and will stop spinning at normal CPU temperatures.
The fan also has a tendency to get plugged up with dust, so I started air-spraying every couple of weeks which helped by reducing the CPU temperature more quickly.
This problem persists with 11.04 as well.
If I suspend the system and turn it back it on, the fan will properly kick in at high CPU temperatures and will stop spinning at normal CPU temperatures.
The fan also has a tendency to get plugged up with dust, so I started air-spraying every couple of weeks which helped by reducing the CPU temperature more quickly.