Why not silver?

[PeteRoy]

Silver is more conductive than copper, so why no company is offering a silver heatsink?

If it's the high price of silver then they should make those heatsink for the enthusiasts who are willing to pay anything to get the best.

 

[wisdomtooth]

The Zalman CNPS7700Cu complete-copper heatsink weighs almost 1Kg... Very heavy.

A silver HSF of the same size would be a heck of a motherboard-bender..

 

[CycloWizard]

It's not much better than copper (silver k=419 W/m-K, copper k=385 W/m-K, about 9% higher). The real answer, however, is that when you're dealing with copper and silver, the limiting resistance for heat transfer is no longer the material of the heat sink, but the ability of your system to remove the heat from the surface of the heat sink. If you have a fan blowing its heart out on a copper or silver heat sink, the difference in heat sink temperature will be pretty much zero, as the fan removes heat less quickly than the heat sink can supply it.

 

[Painman]

Silver weighs 17.6% more than copper, so a HS made of copper weighing 1 kg would then weigh 1.176 kg if made out of silver.

Silver currently goes for about $7/troy ounce (31.1 grams) so if you're talking about the cost of 1.176 kg of silver on the open market (before it's made into a heatsink, packaged and distributed) you're looking at close to $265 worth.

I think that for $265+ I could put together one hell of a watercooling setup and blow away any air setup...

 

[Mucker]

Good, simple article: http://store.yahoo.com/bellacopper/metheattrans.html

m

 

[imported_rod]

Yeah, the price and weight wouldn't be worth it. You could do alot of other things with that money.

RoD

 

[Blain]

Originally posted by: CycloWizard
It's not much better than copper (silver k=419 W/m-K, copper k=385 W/m-K, about 9% higher). The real answer, however, is that when you're dealing with copper and silver, the limiting resistance for heat transfer is no longer the material of the heat sink, but the ability of your system to remove the heat from the surface of the heat sink. If you have a fan blowing its heart out on a copper or silver heat sink, the difference in heat sink temperature will be pretty much zero, as the fan removes heat less quickly than the heat sink can supply it.

What CycloWizard said.
If you really want the absolute best in heat transfer, have someone craft you a HS from Diamond. :laugh:

 

[sparkyclarky]

There have been limited production run silver waterblocks from Cathar in the past (such as the Cascade SS), but you'll almost never see anybody outside of a small enthusiast circle go after such a thing, especially in the air cooling market due to a very diminished price/performance.

 

[Blain]

The Silver Mountain was silver plated.

 

[Tiamat]

Also, not many people want to actually machine silver. Since no company would make it, a true enthusiast would make it themselves.

Currently, I am making my own aluminum heatsinks to cool 2 harddrives. Ill show pictures when its done in 2 weeks. The machinest who is doing this for me gave me discount on the work so its free. But basically, 12" x 3/4" x 6" aluminum slab costs about 120$. Each fin takes 30 minutes to make, and there are 18 fins per heatsink (2 heatsinks). Machinests normally charge 60$ per hour of labor.

Do the math, the total charge would be $1080 for the heatsink labor, 120$ for the material, for a total of 1200$. That is wicked expensive for just 2 alumium slab heatsinks, but its a ton of careful slow work. When milling a heatsink out of a solid slab of aluminum, going below 1/8" thickness on the contact surface, and 1/16" thickness of fin can result in the whole thing collapsing on itself whether that is under the pressure of the vice, or the resonation of the piece upon milling.

So, moral of the story, if silver is 7$/ 31.1 grams, and you start with a 4"x4"x4" silver block, i would wager that would weight something like 3kg and the cost to be $675.

Labor would be around 22 hrs especially if the fins are thin, so thats an additional $1320.

If you machine something for 22 hrs you probably want to spend 40 hrs designing it (based on measure twice, cut once).

so, 2000$ for a silver heatsink that has oxidized and lost its thermal conductivity advantage over copper. In addition, good silver may be too soft and bend too easily.

So, Ag is not cost productive for any application.

 

[Greenman]

Danger den has a solid silver water block on their site.

 

[MDE]

Originally posted by: Tiamat
Also, not many people want to actually machine silver. Since no company would make it, a true enthusiast would make it themselves.

Currently, I am making my own aluminum heatsinks to cool 2 harddrives. Ill show pictures when its done in 2 weeks. The machinest who is doing this for me gave me discount on the work so its free. But basically, 12" x 3/4" x 6" aluminum slab costs about 120$. Each fin takes 30 minutes to make, and there are 18 fins per heatsink (2 heatsinks). Machinests normally charge 60$ per hour of labor.

Do the math, the total charge would be $1080 for the heatsink labor, 120$ for the material, for a total of 1200$. That is wicked expensive for just 2 alumium slab heatsinks, but its a ton of careful slow work. When milling a heatsink out of a solid slab of aluminum, going below 1/8" thickness on the contact surface, and 1/16" thickness of fin can result in the whole thing collapsing on itself whether that is under the pressure of the vice, or the resonation of the piece upon milling.

So, moral of the story, if silver is 7$/ 31.1 grams, and you start with a 4"x4"x4" silver block, i would wager that would weight something like 3kg and the cost to be $675.

Labor would be around 22 hrs especially if the fins are thin, so thats an additional $1320.

If you machine something for 22 hrs you probably want to spend 40 hrs designing it (based on measure twice, cut once).

so, 2000$ for a silver heatsink that has oxidized and lost its thermal conductivity advantage over copper. In addition, good silver may be too soft and bend too easily.

So, Ag is not cost productive for any application.

Not everyone gets custom handmade heatsinks for their hard drives.

:roll:

 

[Blain]

Originally posted by: MDE
Not everyone gets custom handmade heatsinks for their hard drives.
:roll:

But if they did... This would be the way to go :laugh:

 

[Tiamat]

Originally posted by: MDE

Originally posted by: Tiamat
Also, not many people want to actually machine silver. Since no company would make it, a true enthusiast would make it themselves.

Currently, I am making my own aluminum heatsinks to cool 2 harddrives. Ill show pictures when its done in 2 weeks. The machinest who is doing this for me gave me discount on the work so its free. But basically, 12" x 3/4" x 6" aluminum slab costs about 120$. Each fin takes 30 minutes to make, and there are 18 fins per heatsink (2 heatsinks). Machinests normally charge 60$ per hour of labor.

Do the math, the total charge would be $1080 for the heatsink labor, 120$ for the material, for a total of 1200$. That is wicked expensive for just 2 alumium slab heatsinks, but its a ton of careful slow work. When milling a heatsink out of a solid slab of aluminum, going below 1/8" thickness on the contact surface, and 1/16" thickness of fin can result in the whole thing collapsing on itself whether that is under the pressure of the vice, or the resonation of the piece upon milling.

So, moral of the story, if silver is 7$/ 31.1 grams, and you start with a 4"x4"x4" silver block, i would wager that would weight something like 3kg and the cost to be $675.

Labor would be around 22 hrs especially if the fins are thin, so thats an additional $1320.

If you machine something for 22 hrs you probably want to spend 40 hrs designing it (based on measure twice, cut once).

so, 2000$ for a silver heatsink that has oxidized and lost its thermal conductivity advantage over copper. In addition, good silver may be too soft and bend too easily.

So, Ag is not cost productive for any application.

Not everyone gets custom handmade heatsinks for their hard drives.

:roll:

And your point is? Im just stating that if the Original poster wanted a silver heatsink, he would have to make it himself. And I also listed my example to show how expensive it can get when you custom make your own, or have a machinest help you out.

It is not like i get my heatsinks custom made for me without me doing any work. I take pride in my work, design, and study of heat transport.

:disgust:

 

[imported_Kensai]

Originally posted by: Tiamat

Originally posted by: MDE

Originally posted by: Tiamat
Also, not many people want to actually machine silver. Since no company would make it, a true enthusiast would make it themselves.

Currently, I am making my own aluminum heatsinks to cool 2 harddrives. Ill show pictures when its done in 2 weeks. The machinest who is doing this for me gave me discount on the work so its free. But basically, 12" x 3/4" x 6" aluminum slab costs about 120$. Each fin takes 30 minutes to make, and there are 18 fins per heatsink (2 heatsinks). Machinests normally charge 60$ per hour of labor.

Do the math, the total charge would be $1080 for the heatsink labor, 120$ for the material, for a total of 1200$. That is wicked expensive for just 2 alumium slab heatsinks, but its a ton of careful slow work. When milling a heatsink out of a solid slab of aluminum, going below 1/8" thickness on the contact surface, and 1/16" thickness of fin can result in the whole thing collapsing on itself whether that is under the pressure of the vice, or the resonation of the piece upon milling.

So, moral of the story, if silver is 7$/ 31.1 grams, and you start with a 4"x4"x4" silver block, i would wager that would weight something like 3kg and the cost to be $675.

Labor would be around 22 hrs especially if the fins are thin, so thats an additional $1320.

If you machine something for 22 hrs you probably want to spend 40 hrs designing it (based on measure twice, cut once).

so, 2000$ for a silver heatsink that has oxidized and lost its thermal conductivity advantage over copper. In addition, good silver may be too soft and bend too easily.

So, Ag is not cost productive for any application.

Not everyone gets custom handmade heatsinks for their hard drives.

:roll:

And your point is? Im just stating that if the Original poster wanted a silver heatsink, he would have to make it himself. And I also listed my example to show how expensive it can get when you custom make your own, or have a machinest help you out.

It is not like i get my heatsinks custom made for me without me doing any work. I take pride in my work, design, and study of heat transport.

:disgust:

Hell you could get a phase change system for that price!!

 

[Tiamat]

Originally posted by: Kensai

Originally posted by: Tiamat

And your point is? Im just stating that if the Original poster wanted a silver heatsink, he would have to make it himself. And I also listed my example to show how expensive it can get when you custom make your own, or have a machinest help you out.

It is not like i get my heatsinks custom made for me without me doing any work. I take pride in my work, design, and study of heat transport.

:disgust:

Hell you could get a phase change system for that price!!

That is correct. And if the machinest were to charge me, I would go with something like water cooling. However, I found the aluminum pieces in scrap heap in the machine lab, and he is a good friend of mine, so its a great opportunity for me to design, and him to make something outta enjoyment. Building stuff from scratch is fun and enlightening at times. I found out the hard way that aluminum twists and distorts heavily when made too thin

 

[Slaimus]

That's why heatsinks are not machined (ok the skived ones are, but that's also a cheaper process), but extruded.