If your computer tower gets very loud when it is turned on (like it is going to "explode" or "melt down,") the cause of that problem is most frequently dust. 

When dust settles in your computer, it works like insulation - making the internal parts of your computer hotter.  Your computer's fan then has to work harder (and louder) to keep your tower at a safe, cool temerature. 

The simple solution to this problem is to purchase a can of compressed air and blow dust out of the inside of your computer.  This usually quiets things down.  Alternately, the problem may simply be stemming from the vents on your computer tower being covered.  Double check you do not have any papers or other materials covering your computer's air vents.

In most cases, the loud fan is not harmful, though over time, if your computer gathers more dust or remains very dusty, your fan may burn out from working so hard.  A burnt-out fan can cause computers to overheat and randomly shut down.  If you begin to encounter this problem, please call the Help Desk at 1-877-PALCS-TLC.