Overheating PB G4?

[holly sisson]

I've noticed, in the last few weeks, that my G4's fan is on a lot more 
then it used to be. I'm also noticing a lot of heat under the function 
keys and it's even warmer above them on the actual casing. Is anyone 
else experiencing this?

Thanks for your help,
Holly
PB G4, 667 MHz, 768 MB, 10.2.8