Hey, i am an owner of a 2009 Mac Pro (2x2.26, 4.1). Because i am a friend of cool systems, I changed my graphic card fan and added an active cooling system for my RAM. The only hot parts of my Mac are still this mysterious northbridge chips (with ca. 70 °C). So is my questions: Where are this Northbride chips? A simple picture would be awesome. I ´ve recently read many debates about the heat of the Northbridge, but nobody wrote, where there are. So I don´t want to start a new thread concerning the topic, how hot the northbridge chips should be.