Unplugging northbridge fan... meltdown?

My northbridge fan has become increasingly louder and louder to the point now where its buzzing pretty irritatingly.

Im running a 3000+ on a msi k8n neo4 (an older setup), will unplugging the northbridge fan cause meltdown? I dont game anymore, and this computer really doesnt see much heavy use

yes, a meltdown could occur even if you are not playing any games. A better solution to your concerns is to buy a passively cooled northbridge heatsink (no fan). I think Zalman has a good one.