So my PowerBook G4's hard drive has one foot out the door (its making noises) and its time to replace it. I mean, its original from January 2005, so its going on 8 years old.

My question is, I was strongly advised not to put a 7200rpm in my iBook G4 by you guys because the heat could warp the plastic. Now, the PowerBook is made out of aluminium, but could the heat the 7200rpm drive puts off damaged the computer in any other way? Or should I just get a new 5400rpm one?