Hi, Matt.  We were talking about - -

 JH> But about that shorting out - - I see where a number of vendors
 JH> sell a "copper shim" for use between the heatsink and
chip.  I wonder
 JH> how those work without shorting things out?

 MM> Intersting!  The concept itself seems flaky, as that would introduce
 MM> _two_ additional surfaces with 'air-gap' potential.  If it is actually
 MM> made of copper (which is both conductive and relatively hard), that
 MM> would give it three strikes in my NSHO.

I did a bit of research at Thermaltake's website - - their "shim" for
Athlon/Duron is BIR 0.6mm thick, copper, and it has cutouts for those 4
rubber pads, plus cutouts to miss the surface-mounted components on the
chip's 'board'.  The purpose looks to be just to add stabilization the
heatsink over the chip, which would make some sense in the case of those
heatsink/fan combos which just have the single clip-ons to the mainboard
socket, at each end.  The mounting concept for some, like Thermaltake
6Cu+ I have here seems rather bizarre - - with a very strong spring/clip
with 2-point attachment, over a cpu chip with a tiny metal plate over
the die to send all that heat out, all on a single axis, with the
big-butt heatsink and fan just kind of teeter-tottering over that
3-point axis. I guess the point of those 4 small round rubber pads is to
keep if from tipping too far to either side.

Some of the other HS&F combos, like a Thermaltake Slim Volcano 8SE I
have here, use 3-point connection of the hold-down clip to the
plastic tabs on the mainboard's ZIF socket.  I like that concept a lot
better.



 MM> The packaged Intel P-4s come with a "shim" also, which
appears to be
 MM> about a .003" thick lead strip covered with a thin brown 'powdery'
 MM> coating glued to the heatsink by it's edges.  Those heatsinks are NOT
 MM> for thin MBs though, as they are cam-latched to the MB, and deflect the
 MM> MB about an eighth inch when they are locked down.  Intel warns that
 MM> cheap MBs could become sufficiently distorted to contact the metal case
 MM> beneath the MB.

Ouch!  Sounds like another 'skating on thin ice' solution.  I'd have
thought Intel would do better than that.  That coating sounds like some
of the "Bergquist material" I've seen.  Those may work well for one-shot
installations, but the Bergquist pad on bottom of Thermaltake Volcano
6Cu I took downtown to do some Athlon/Duron mainboard testing got pretty
much completely torn up and destroyed in the area of the "die" after a
couple of installations and removals.  So we scraped it all off the
other night, and now it is back to plain old white thermal grease.

- - -  JimH.

... Jim, I only got 2 parts of me getting bigger - earlobes and belly- Bubba
--- MultiMail/MS-DOS v0.32