Hi there, I just purchased my first mac...the new 3.06 ghz iMac. I was wondering if I should be concerned that the Northbridge temperature is consistently in the 70s C when all other temps (including Northbridge 1) are between 40 and 60 C? I haven't tweaked the fan settings at all. I did notice that it gets pretty hot on top after a while. Any advice would be greatly appreciated. Thanks!