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Unread 11-18-2005, 04:28 PM   #53
Cathar
Thermophile
 
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Join Date: Sep 2002
Location: Melbourne, Australia
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Actually Bill, it was Jaydee that postulated the durability.

I am questioning the effects of block geometry, and the applied pressure and deviations in effect as a result of this. 1.5mm thick copper flexes fairly easily, we know this. The edges of the IHS are mounted against the packaging substrate with a compressible bond. The IHS will warp and flex in accordance with the pressures, and locations of the pressure applied as a function of the block geometry.

You talk about deformation of the IHS and the bp, and I agree, and that is precisely the issue here. If the IHS is deformed in a convex fashion (with respect to the heat die) then the center of the IHS, where the heat probe is, is measuring a point on the IHS that is pushed hard against the block and not against the heat die, instead the edges of the heat die serving as the major point of heat transfer. If a block is convex (or at least less concave) when under mounting pressures, the reverse would be true.

Given such variations, I must express a great deal of frustation about this line of reasoning. The CPU die is NOT the IHS.

I am particularly perplexed by this comment from you:

Quote:
Originally Posted by unregistered
the die temp is a fiction
Sorry? Just what is it that we're trying to cool here?
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