copper shim vs. thermal pad

[Timothy Daniels]

I'm putting a different motherboard in my XPS M1330 -
the motherboard without the discrete nVidia graphics
chip. I find that there is about a 1.6mm gap between
the Intel system chip and the heat sink that is attached
to the copper heat pipe. I don't want to tighten the gap
down because that would put a tipping force on the CPU
heat sink junction, but 1.6mm seems like it would be too
large a gap for a thermal pad to conduct heat away well.
So I'm looking into using a copper shim - 1.5cm x 1.25cm
and either 1.5mm or 1.2mm thick. Are there any caveats
about using a copper shim? Are they better than using
thermal pads?

*TimDaniels*

[Happy Oyster]

YES !!!!!

Many "copper" things are beryllium bronze, which is EXTREMELY poisonous.
I know a man whose wife was poisoned. Her case is known in the US
medical archives. She worked in a dental lab and got the debris
particles from material containing beryllium into her lung. THAT is the
crucial thing: DO NOT INHALE DUST!

So, if you use "copper", try to find out if it really is PURE copper or
a compound containing beryllium.

The "thermal pads" have very bad thermal characteristics. Their sole
purpose is to close air gaps, and so they must be pressed by great force
to be very thing. 1.6mm is by far much too much for any thermal pad.

Very good copper sheets can be found in shops for do-it-yourself where
the copper is meant to be used for hammering vases and other stuff. Some
cm2 of surplus material should be cheap. But you have to be extremely
cautious about the surface and oxidation. I would use a piece of such
copper PLUS some thermal paste (expression correct ?) to better the
contact between the metal surfaces.
--
TG_1 pwned by FRAUENPOWER
----------------------------------------
http://www.transgallaxys.com/~kanzlerzwo

[Timothy Daniels]

"Happy Oyster" <-*-*.@.*-*-> wrote:

Interesting about the beryllium. I do not intend to saw or grind or file
the shims, so I guess that is a moot point, but I wonder if that is why no
large U.S. retailer carries copper shims - which all seem to be made from
recycled material.

*TimDaniels*

[Larry]

I wonder if the old copper "wheat" pennies are pure copper?

[Larry]

Just checked on it myself...all pennies 1982 and before are 95% copper...just a thought.

[Timothy Daniels]

"Larry" wrote:
> Just checked on it myself...all pennies 1982 and before are 95% copper...just a thought.

Some were. The rest, and all since 1983, are 97.5% zinc.
http://en.wikipedia.org/wiki/U.S._penny

Please remember that the original questions were:

"Are there any caveats about using a copper shim?
Are they better than using thermal pads?"

*TimDaniels*

[Timothy Daniels]

"Timothy Daniels" asked:

I've finally installed the used motherboard without
the nVidia graphics chip. It runs a little cooler than
the original motherboard that had the nVidia chip,
and I see no difference in YouTube videos of wingsuit
flying than when I watch them on my Precision T3500
workstation.

I used a 1.2mm thick copper shim with thermal paste
between the shim and the Intel system chip, and 0.2mm
thick Dell thermal pad between the shim and the chip's
heatsink. That combination put the least bending torque
on the heatpipe so the CPU heatsink would remain flat
against the CPU. Between the CPU and its heatsink I used
thermal paste.

Running YouTube wingsuit videos for half an hour caused
no speedup of the fan or any anomalies in the video display.
That's all the video performance that I need, and I wish that
I had not gotten the troublesome optional nVidia graphics
chip in the first place.

*TimDaniels*

[jodie.c...@gmail.com]

I recently repasted the heatsink on my XPS M1210 and the gpu portion utilized a rubber pad to fill the gap between the gpu and heatsink. Unsatisfied with the mediocre performance of the pad I started looking for a source of copper to use as a shim. My final solution was to use a pre 1982 penny for the 92% copper content and a near perfect size. I filed both sides smooth, applied as5 to the gpu and heatsink and reassembled with the penny replacing the rubber pad. Since I did it I've noticed drastically reduced temperatures and performance has become more stable due to decreased temps. This won't get you any significant increases in performance but you'll notice a difference.

[Ben Myers]

On Sunday, December 1, 2013 9:16:18 PM UTC-5, jodie.c...@gmail.com wrote:
> I recently repasted the heatsink on my XPS M1210 and the gpu portion utilized a rubber pad to fill the gap between the gpu and heatsink. Unsatisfied with the mediocre performance of the pad I started looking for a source of copper to use as a shim. My final solution was to use a pre 1982 penny for the 92% copper content and a near perfect size. I filed both sides smooth, applied as5 to the gpu and heatsink and reassembled with the penny replacing the rubber pad. Since I did it I've noticed drastically reduced temperatures and performance has become more stable due to decreased temps. This won't get you any significant increases in performance but you'll notice a difference.

Heat is definitely the enemy of the nVidia graphics chips on the XPS M-series many other Dell laptop models, plus Apple and HP laptops. To reduce heat even further at a smallish sacrifice in graphics performance for most applications, give the MSI Afterburner a try. But do something different. UNDERclock everything you can, reducing the speed of the GPU itself and memory. Heat is produced in proportion to clock speed. Cut clock speed by 20% and you reduce heat by 20%, more or less.

Of course, the original raison d'être for Afterburner and similar utilities is to pump up the graphics subsystem to the max, achieving greater frame rates and more realistic graphics in video games. Interesting tradeoff for laptops: longer life vs faster graphics. With a laptop, the choice is a no-brainer for me. With a desktop, hey, you can always replace the nVidia card that went up in smoke... Ben Myers

[c.c...@free.fr]

I replaced thermal pads on a nvidia GPU with copper shim made out of copper plumbing pipes thermal paste on both sides of the shim works fine and certainly not toxic