Passively cool the nforce3 chipset ?

I've noticed the little fan/sink chipset combo on my MSI K8N Neo2 , and I did replace the thermal pad on it with AS5 , but honestly the thing never even gets warm . I have one of these Zalman NB heatsinks in my "cooling" bucket and I've recently caught the total silence bug ... can the nforce3 be passively cooled under oc'ed settings ? Basically im looking for someone else who's tried before I slap it on there