i have to restart it like 5 or six times in order for it to return to it's normal low hum. it's like five years old.

It's likely that the noise you are describing is your computer's fan. Sometimes, as a computer ages, your fan can become clogged with dust, or just generally begin to make noise. Sometimes this can be fixed by simply opening up the console and using compressed air to clean the fan off. You should turn off your computer before doing this.

Source(s):
Personal Experience with aged computers.