I recently had to get a new motherboard because i fried my old one. Everytime i do something like, load up a program, change pages on a web page my cpu fan starts making a noise as if its "revving" up or strugeling. Why would it be doing this the fan is about a year and a half old. My CPU is has a 266 Mhz FSB but my MOBO only has a 200 Mhz FSB. Do you thing this might be an issue of the cpu putting more demand on the Bus then it can handel and making the fan work harder or something?

dont think so i think it is just wore out my old p166 fan did this i think fans only last so long before they give up you could try peeling the sticker of and putting a drop of machine oil or some wd40 in it then cover it up with tape

I wouldn't suggest putting oil on the fan. It's just going to make a freakin mess inside of your computer. Just go out and get a new cpu cooler/fan. They wear out just like anything else, some sooner than others.

Also, check out for sure if you are hearing your ROM disk firing up. sometimes mine does the same thing when I first click on a program - I don't know why, but it takes a few seconds and sounds like an airplane warming up. Then it runs quietly rest of the session.