Mobo fan not working nf7-s 2.0

Hey Guys

While upgrading to the newest version of ubuntu, its completely messed up my primary drive due to a bug, which has been reported and I'm having to format it and reinstall everything.

I've decided to buy a new 500GB backup drive before I do this as I can still access my data from a live cd.

However when poking about my computer to work out which drive to buy, I noticed that the fan on my motherboard (still using the oldschool abit nf7-s v2.0) is not working and not spinning. This is the one on the motherboard chip (not the cpu fan!).

I'm not sure how long it has been like this, but my case has a few fans so isn't amazingly hot. How worried should I be about this? Should I just leave it and cross my fingers, or should I take some action (which I'm not too keen to do as my computer can be a bit tempramental)?.

The good old Zalman Passive. Excellent for the NF7 and only about £4.

Cheers, the emergency is over now, after I removed all the dust which had gathered between the blades it started working again :)