Improve the TIM joint?

[bigben2k]

Originally posted by hara
Why don't you try this shin etsu stuff.

Another TIM idea I had was to use gold leaf between the CPU and cooler.

The reasons are simple: Gold is a very mallable material and with compression *could* make a good TIM. The leaf is only a few microns thick.

Gold's thermal conductivity isn't bad at all. It is better than aluminium but not quite as good as copper. If you calculate the thermal resistance for that short distance, the difference between it and silver would be negligable IMO.

I saw a thread on [H] once about using al foil. Some people got quite good results since the foil is adaptive. That is why I'm suggesting gold leaf now.

I might try the Shin Etsu, if I can find specs for it.

Maybe this thread should be turned back into listing various products, and specs?!?

You go ahead and try gold or Alu. I think I'll stick to tested and proven products, for now.

[jaydee]

Originally posted by hara
Why don't you try this shin etsu stuff.

Go here and it has specs on the shit etsu and AS. It it pretty amazing to me people see alomost a 6C gain from something with much less thermal condictivity.

Claimed Thermal Conductivity (W/mK)

Arctic Silver LLC Arctic Silver 4.65 - 5.15

Shin-Etsu MicroSi G-749 Thermal Grease 2.9

I think this just goes to show you to many people apply way to much Silver compound. You need an ever so thin layer of it. Less the better. It just needs to fill in the gaps.

[hara]

@JayDee: I meant the shin etsu G751.

@BigBen: I'll try out Al foil first and see if it does make a good TIM.

[TallTxnMo]

Just got a new Tbird 2400+ and tried the new AS Ceramique. Never got it to boot. When I pulled the cpu, found that it had been fried. Now, this isn't the first time I've changed a cpu or mounted a HS or WB. The stuff seemed awful thick. I wonder if the Ceramique is what fried my processor.

[redleader]

Originally posted by TallTxnMo
Just got a new Tbird 2400+ and tried the new AS Ceramique. Never got it to boot. When I pulled the cpu, found that it had been fried. Now, this isn't the first time I've changed a cpu or mounted a HS or WB. The stuff seemed awful thick. I wonder if the Ceramique is what fried my processor.

I've seen people use toothpaste as a TIM. The paste didn't fry your CPU. Poor mounting did most likely.

[jaydee]

I have mounted HS/blocks WITHOUT any thermal compound several times and never fried a CPU. And I assume you mean XP2400+ as T-Birds were phased out at 1400mhz.

[prb123]

Originally posted by N8
5 mm? Holy crap that is pretty thick. I am guessing you mean 5 micro meters (microns)? You could do that (5 microns) with a sputter deposition setup, but I don't have one with easy access.

The other problem that could occur once you start growing/depositing/layering metallic layers is that they could de-bond or flake off and some point in the installation or removal and then you have a problem with a very conductive particle(s) on your CPU/mobo.

I think he wants to know about creating the water block directly on the die. Virtually eliminating the TIM.

How thick of a deposit would you need to create a Cascade type block? How would you seal it? Is there a way to create a form to grow the base inside of (ideally we would not want to machine this)?

[utabintarbo]

Originally posted by prb123
I think he wants to know about creating the water block directly on the die. Virtually eliminating the TIM.

How thick of a deposit would you need to create a Cascade type block? How would you seal it? Is there a way to create a form to grow the base inside of (ideally we would not want to machine this)?

Now that would be cool! A "grow-your-own" waterblock!

[satanicoo]

if there's 8 degrees on the TIM, this is probably a very good way to resolve the problem, thats why i sugested it.

Still, quite impossible to achieve.

[N8]

Originally posted by Cossey3
Just how flat is the amd core are we talking a few microns or <1 micron
and if the amd core is flat enough if we were to get the base of the heatsink or waterblock to a similar flatness we could do without the paste.

You could do without the paste ONLY if you were flat enough AND polished enough.

Flat does not equal polished.
Polished does not equal flat.

You have to be an expert at both if you want to get rid of any paste.

For the average and even above average person, I recommend heatsink paste. Just put enough on to fill any air gaps, not enough to form a separate layer.

[BO(V)BZ]

In case anyone is curious, I got my TIM from Thermagon yesterday. They sent me a sheet about 2" x 8", so I should have enough to play around with. Don't expect any results very fast, I'm slow at doing things =]

BO(V)BZ

[nicozeg]

Originally posted by satanicoo
if there's 8 degrees on the TIM, this is probably a very good way to resolve the problem, thats why i sugested it.

Still, quite impossible to achieve.

And what's the source for that 8º number? I suspect something wrong with that.

[jaydee]

Originally posted by nicozeg
And what's the source for that 8º number? I suspect something wrong with that.

Very first post of this thread.

For example, for an 80W 100mm^2 heat source on the White Water with 10lpm flow rates, the total temperature rise is ~14.0C. Of that 14.0C, 8.0C is due to the thermal paste, 1.5C is due to the copper base-plate itself, and 0.1C is the amount that the water would be heated up by. Those are all values that can't be altered. So the 4.4C that remains is a measure of the efficiency of the block at 10.0lpm.

For the Cascade, that 4.4C is being brought down to around 2.5C, and it's taken a LOT of refinement using the most efficient known way to use water to cool (impingement), to get it that far.

I've come to see the Cascade as the final destination in my water-cooling journey.

Doesn't say where the 8C is comming from though. guess will have to ask Cathar as he said it.

[nicozeg]

That's my point, the whole thread is based in information that may be better to revise

[bigben2k]

I think I'm getting through the Thermagon sales rep, for a sample.

Here's the stuff:
http://www.thermagon.com/pdf/T-pcmHP105.pdf
(PDF, 1 page)

[satanicoo]

OK. 1 question only. is it 8 degree on the TIM or not?

[bigben2k]

See the first post. If you have further Q's, start another thread.

[satanicoo]

Originally posted by bigben2k
See the first post. If you have further Q's, start another thread.

WOW! Tuff one
Just checking, since this doubt is in the air:

Originally posted by jaydee116
Doesn't say where the 8C is comming from though. guess will have to ask Cathar as he said it.

[redleader]

http://www-esg.lbl.gov/esg/personnel...nsoldering.pdf

Take a look at the indium-bismuth solder. The eutatic point occurs at 78C for a ~79% indium solder. Meaning we could use it to solder a waterblock directly to the CPU die without cooking the CPU (which is typically rated to at least 90C). It also lists a few more exotic solders with even lower melting points.

The pdf mentions typical difficulties in soldering silicon, however it also proposes a solution. Add a thin metallic coating to the silicon die and then solder that.

Does this look viable to anyone else? I'm pretty tempted to go and get some of that solder if I can find it anywhere. The intermolecular bonding in solder should allow for conductivities an order of magnitude greater then at present.

[flyingass]

redleader,
that sounds like the most viable idea so far in this thread. Silver nitrate as discussed earlier could be used to form the thin metallic film on the die fairly easily. About the only challenge to making use of this sort of thing is confining the solder to the immediate area surrounding the die. we're all creative here though, so a solution wouldn't be much trouble.

What's the cost of this sort of solder?

[redleader]

No idea. However from what I gather its being used in extremely low cost electronics (less power to solder it), so I doubt its very expensive-in bulk at least.

Trick would be doing the solder and install without cracking the solder layer, I imagine it would be fairly brittle.

Maybe I should start a new thread to discuss this idea?

[bigben2k]

Originally posted by redleader
Maybe I should start a new thread to discuss this idea?

Nah, go with it. This is the most feasible I've seen yet.

Let's see if we can score some of this stuff.

[jaydee]

Originally posted by redleader
http://www-esg.lbl.gov/esg/personnel...nsoldering.pdf

Take a look at the indium-bismuth solder. The eutatic point occurs at 78C for a ~79% indium solder. Meaning we could use it to solder a waterblock directly to the CPU die without cooking the CPU (which is typically rated to at least 90C). It also lists a few more exotic solders with even lower melting points.

The pdf mentions typical difficulties in soldering silicon, however it also proposes a solution. Add a thin metallic coating to the silicon die and then solder that.

Does this look viable to anyone else? I'm pretty tempted to go and get some of that solder if I can find it anywhere. The intermolecular bonding in solder should allow for conductivities an order of magnitude greater then at present.

So your going to try and solder an Aluminum die from the CPU to a Copper water block?

[Since87]

Originally posted by jaydee116
So your going to try and solder an Aluminum die from the CPU to a Copper water block?

I didn't see aluminum mentioned.

I believe the idea is to plate silver onto the silicon of the die, and then solder the die to the block.

I have some reservations about the idea, but it's interesting.

It would be a good idea to look into the differences in the temperature coefficient of expansion of copper, silicon, and indium/tin solder. It may be that the die would be cracked by the contraction of the waterblock as the soldered die/block cools down from soldering temperature.

[jaydee]

Originally posted by Since87
I didn't see aluminum mentioned.

I thought they used aluminum in the die. My bad.