Hi Jaden,

The point of a CPU fan is to keep your CPU within certain temperature limits. The hotter it gets, the faster your fan will spin. At least, that's the way it is supposed to work.
I would first check that your CPU is not overheating. There are many third-party utilities that will measure this for you. HWMonitor from CPUID is a good one.

If you discover that your CPU is running hotter than it should be, then your next step is to learn the cause. You can use Task Manager (Windows) to see what is using the most CPU resources.

Another thing to check for is dust. Dust will build up over time and clog up the heat-dissipating fins of your heatsink. The fan itself can get gunky, too. If you find a dust build-up, get yourself some canned air, turn off and disconnect your computer, and start a cleaning project.

Check the fan settings in BIOS. Who knows? Maybe they've changed for some reason. There are also third-party utilities you can get free of charge that will manage fan speeds for you. One popular choice is SpeedFan from Almico.

I hope this gets you on the right track,
Richard

Glad to hear it, Jaden