Zalman has a passive heatsink for the northbridge I believe.
They might have something else too with a fan.
People have used the passive solution with no problems and less noise.
I've got a spare Abit hsf but am getting the Zalman hs also.
From what I'm hearing it's only a matter of time when the fan fails not if.
Yes... I have my 2.4C running at 3, with a passive NB.... I used the Zalman (the yellow/gold one) and used a scroll saw to trim a couple of the corner fins off so I could use the circular mounting bracket... haven't had a bit of trouble, even through a move, and a few trips to my brother's house for gaming... I just lapped the bottom a bit, put down some Ceramique (sp?), and put the passive sink on... much quieter than the hairdryer on that original stock NB cooler...
If you check back in the forum, there were a lot of HOWTOs and discussion over this... many had pictures.... you just need to "dry fit" the sink to make sure that they little spring clip is not under soo much tension that it rips those little hooks out of the board... I used a small file to fine tune it....
BTW, my P4 is folding with 2 instances, so 100% CPU usage... and it's on 24/7... haven't had any trouble...
Hmm, last time i tried doing something, I messed up my stock nb hsf;p So i'd rather not do any modding stuff.. And I understand that zalman's hs doesnt fit on IC7 without modding, right?