CPU cooling bottleneck?


Jun 6, 2008
Has anyone seen any literature discussing where the greatest thermal resistance occurs in cooling a cpu. I have been thinking about cooling a CPU as a basically a circuit with resistors, where each resistor represents a a thermal resistance that is impeding heat flow from leaving the chip.

The major resistances I can think of in a cpu system include the resistance from the chip/chip housing thingy to the base of the heat sink (thermal grease zone), the resistance to conduct heat from the bottom of the heat sink to the fins(heat pipe zone), and then the resistance brought on by trying to remove the heat from the fins by way of airflow(fan zone). I was wondering if anyone knew which is the biggest problem when trying to cool a chip.

Is it transfer from chip to sink?
Transfer from bottom sink to top?
Transfer heat from sink to air?



Feb 9, 2008
I'd place it at chip to heat sink, because we all know the chip can get hot! But there is no way for the full heat to xfer to the sink.

Wonder if you can fuse the IHS with the heat sink contact area! (And then I wonder if that would help!)

But I would place my wager that IHS to sink would be the main problem, other than the fact that the thing just has to put out huge amounts of heat, thanks to the spacing between the transistors in the chip.

We need a new heat sink design!!

I recommend looking on Intels site, and then reading their thermal guide, as well as their instructions and specifications that heat sink manufacturers of market heat sinks have to follow.

Processors are some picky pieces of machinery!

So good luck!