It is just pure physics. Every material on earth conducts heat (and
electricity) at different rates based on there electronic make up. Generally
speaking, metals are high, organic low.  However, among the metals there is
also a range. The relative order is as follows with air being 1.

Silver        16211
Copper        15124
Gold          12019
Aluminum       8920
Alun Alloy     7042
Zinc           4266
Silver Grease   280
Zinc Grease      24.3/16.7
Elastomer Pads  <16.7
Air               1


I like to use the example of sitting in school with a room temp of 70° at
one of these combo seat/desks and moving your bare arm from the plastic desk
top to the metal support and reacting to the "cold" metal. Although the
metal support felt colder in comparison to the desk top portion, and even
the air felt warmer than the desktop portion,  in fact the air, the desktop
and the metal support are all at the same temp but have different thermal
conductivity.

To answer you question about what temp the CPU needs to operate to get a
10°F lower temp with Silver grease Vs. Zinc grease, without getting into the
actual formulas, real world test show anytime the CPU is operating above 50%
utilization. Above 50% utilization, the CPU temp at the top center of the
CPU (using recommended cooler and grease) will general range from 122° to
160°+ depending on many factors.

I hope this satisfies you doubt <G>.

Daniel Wysocki
Twin*.*Star Computers
770-498-2582 / 800-816-0663
[log in to unmask]
Fast - Reliable - Wallet Friendly



-----Original Message-----
From: Allen Glenn <[log in to unmask]>
To: PCBUILD - Personal Computer Hardware discussion List
<[log in to unmask]>
>
>At what temp would the CPU have to be operating for the silver paste to
lower the
>CPU temp 10°F over the zinc paste with all other environments equal?
>
>It just does't seem possible that a material that is maybe .001 inch thick
could
>perform that much better at any normal CPU temp when both are designed
>for the same purpose.
>
>         PCBUILD maintains hundreds of useful files for download
>                     visit our download web page at:
>                     http://nospin.com/pc/files.html

                         PCBUILD's List Owner's:
                      Bob Wright<[log in to unmask]>
                       Drew Dunn<[log in to unmask]>