Hey guys. Im running on an old msi 939 nforce4 motherboard. The little fan over the motherboard chipset died out around 2 months ago but my computer has NOT had any bsods, lock-ups, freezes etc. Will my chipset fry eventually if I dont get this fixed? Thanks

Check the temperatures on it if possible to be sure it isn't running to hot. It might be that it can be run passively. If you want to be safe, buy a new cooler for it and install that to keep temps down and insure that it won't overheat.

I checked the temp. The northbridge chipset is running around 40C. Is this ok?

That is fine, but is that at system load or idle? You might want to try running Prime95 for a couple hours then check the temp again.

You should be able to get a replacement chipset fan for $10 or so.
Another option is to try to fix the old fan by carefully unpeeling the sticker covering the center hub, and adding a drop or two of oil to the axle you'll find there.