Replace the NB fan, the NB Fan/Heatsink assembly, or get a fanless NB cooler - normally significantly taller, but good if you are aiming for a quiet system.
Some Northbridges need a lot of cooling, some need less, especially if not overclocking, or running at less than maximum FSB and memory clock. On the other hand, many run excessively hot, due to badly applied low quality paste
Just found a review...
Weird looking Northbridge cooler, not the good old diagonal push pin fitting.
It appears that the fan can be thermally controlled (Faneq on), and since it suggests that the active cooling enables them to have a smaller heatsink, it wouls seem that it is most definitely needed, and it does not look well placed for making use of sidesplash airflow from the CPU heatsink.
It looks like it may be difficult to match!
http://www.extrememhz.com/IC7-G-p2.shtml - another review, and an entirely different appearance