replying to Robert Green , DCB wrote:
robert_green1963 wrote:

wrote in message
stuff snipped
I've got a bunch of heat sinks/cooling fans for CPUs and some of them did
have a highly polished copper insert that sat right on the chip (with
thermal gunk - amazing how much of a difference that stuff makes!)
But by and large they were mostly huge junks of aluminum. There were also
sinks that had a bracket that allowed use of a slower, quieter (and harder
to plug with dirt) 80cm cooling fan suspended over the CPU. I bought a
lot
of spares and then switched almost exclusively to tablet PC's I got from
Ebay. )-: Not sure what to do with all those spares and for that matter
all
the SCSI cards, 10Mb NICs, Archive tape controllers (a whopping 250Mb of
backup tape - huge for its time), old modem cards, ISA controllers, EISA
controllers, SCSI cables (I, II and III) and a host of other stuff from
days
gone by. Did I mention my wife says I am a hoarder?
(-:
--
Bobby G.




If you cut them open you will find that any decent heat sink for high
speed processors all have copper heat tubes and copper exchangers. They
can have aluminum fins but the heat exchange is copper, why? because
copper has 2x the thermal exchange of aluminum.

Also I find it interesting that the Carrier article is about evaporator
coils not condenser coils, yet its the condenser coils that are being
changed to aluminum while almost all of the evaporator coils remain copper.






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