hamfest, i was having the same problem with my inspiron 1150, with exception of the rattling fan.   I have had mine now since the summer of 2004 when i went off to college.  I just tried this and i am just shocked at how well it worked.  First download Notebook Hardware Control, its a free software that lets you moniter your hard drive temp, your CPU temp among other things.  After you install it, really load down our computer and get it to its "maximum" temperature jsut to see what it can get up to.  Mine was getting up to about 76~78 C.  I then removed my keyboard and thermal cooling unit (directions are on this website) and really cleaned it out with compressed air, Youd be suprised on how this will affect your airflow, or at least it suprised me.  I then put arctic silver 5 thermal paste between my processor and thermal cooling unit, and the GPU.  After putting my laptop back together and running windows media player, virus scan, internet explorer.. ect.. it now only gets to 54 C max.  Incase no one else notices THATS OVER 20 C!!!  Needless to say it totally fixed my heating problem.  But who knows, maybe mine was just a rare simple case.  By the way if you do decide to do this check out arcticsilver.com.  They have instructions for using their thermal paste, and dell has the manuals for dis-assembly. Hope this helps!