biting my tongue, mouth filling with blood; choke choke

godamn sports, 'we' need to think about what is read

MadDog: go read this!

Let's put an end to this now, before BillA keels over...

Just took in myv65's bit he wrote, of course!, the Alu would have a huge surface area compared to the Cu...

Where do you think the Alu cools better myth came from then?...

BB, sorry, I tried reading through that a couple times before. I never knew you could make scrambled eggs so 'cotonwool light' from brains before! :) ...

I have been seeing it on any number of idiot 'hardware review' sites for 2 1/2 years, or better
truly it is one of the most pervasive pieces of dis-information in the WCing world

aluminum is cheaper and less costly to fab
but if its not being shot into space, who cares if its lighter ?
(yea, I know, the max hsf weight limits)

any cooling product of aluminum needs to have a price 'advantage', for it will not have a performance one

Amen to that !

It's truely annoying!, when you can't actualy test something yourself,~ to try to find out the truth of it, and you read it at so many sites telling you 'X is true', to find out afterwards it was aload of boldrix :( .
Makes you wonder/realise how much is plaugerised from one site to another then accepted as gospel :rolleyes: .

Well on our quest for truth, be thankful we have BillA, he may not be gentle, but you get there in the end :D ...

all are well advised to spend the time and effort to absorb Dave Smith's (myv65) articles
he is far more 'gentle' than I (and a better writer)

Anyone is free to quote anything I write in any forum or article. More often than not, it'll even be right, though I admit I am not infallible.

In the very first of my articles I tried to imagine the common sources for the Al vs Cu myth. I suppose what really gets me is two-fold.

One, so many people still insist that aluminum is better at getting rid of heat while copper is better at absorbing it. Yeah, like metals have a brain and can decide to behave differently depending on which way heat is travelling. This is nothing more than confusion over transient vs steady-state conditions. Two, aluminum does have an advantage in the right situation. In air-cooling especially, the thermal resistance of convection largely dominates. This makes aluminum the winner when handled properly. Only when conduction through an unchangeable and small cross section (read: from a die) is important does conductivity really matter much. If you can afford (or make your own from) all copper, it'll always win an "identical shape vs performance" test. If you can't meet those specs, aluminum has its place.

So true, and the bad thing is alot of aluminum or alu/cu products are MORE expensive. Thermalrights coolers seem to always be at/near the top, and they are so CHEAP, too. You can grab a 30 buck sk-7 with a not-too-noisy fan for so cheap, and that will get you a pretty darn good overclock.

Modesty too!! :D ...

Transient?, is that after the heatsource has been removed?. I recon ALu cooling faster after heatsource removal has to be the source of the AL/Cu thing/myth , they just carried it over to heatsource~continued without thought!.

I was trying to imagine ALu having the same density as Cu when I asked the 'BillA choker' question :D , if it was somehow compessed to the size & shape of Cu, I thought it would cool down afterheat the same.
Is heat storage directly related to density?, how far apart are ALu & Cu with conduction?, I know Cu is better but by how much?, do you think density plays any part in that?. is Lead any good for conducting?.

I should let you read his comments about the recent Bears/Packers game. Was nothing gentle there.:eek:

:D

ahh soo,

and here I was thinking his patience was boundless, kindness without limit,
with understanding and compassion for even the most challenged

but I guess not for $1,000,000 athletes
(ok by me)

Ah, more potential sources for confusion. "Storage" related properties are tied to mass, ala specific heat. "Transfer" related properties are tied to geometry, ala conductivity.

Density has no inherent role in determining specific heat. In pure forms, aluminum's specific heat is actually higher than copper's. As you have already noted, however, equal size blocks of each show that aluminum cools more quickly. If you could somehow compress aluminum to match copper's density (without changing any other property :rolleyes: ), then an aluminum block would hold more thermal energy than a copper one.

Lead sucks for heat transfer, as do most other metals in comparison to silver, copper, gold, and aluminum.

If you really want to get into the "why" of all this, you'll need someone with skills much different than my own. This gets into the realm of crystalline structure, atomic considerations and a whole heckuva lot of other stuff that I hardly know the basics of.

What? Sarcasm from Bill? LOL.

And what $1,000,000 athlets? I had assumed the Bears players all missed the flight and the unpaid Illini players had suited up in their places.

lol

I remembered it as high school kids, but I'm old, you could be right. LOL Just a shot of humor, I couldn't resist the opening. Don't get many with Dave. :D I'll go back to silent mode now.

It's strange that they're all non~ferrous, with a direct comparison of quality to 'disolvability'. ALu corodes quickest, then Cu, I don't know about Gold or Silver but don't they tend to tarnish rather than corrode(?). perhaps some kind of Cu~gold/silver Alloy is what we need?...

PS, Cu corodes in the long run does'nt it?. I seem to remeber seeing bits dug up (or from the sea) that were once armour, ect...

Gold is the beauty of metals: it doesn't corrode or tarnish.

Silver tarnishes very quickly.

Tarnishing and corrosion are basically the same, as long as you consider "corrosion" as oxidization, which is a more accurate term.

What I meant was Cu tarnish seems to be protective to the metal underneath, but the ALu I've seen seems to 'weaken' (like when it snaps first or second bend, rather than retaining it's 'elastisity')regardless...
I see them as different(even though I know you're right) both are oxidisation, but tarnish is surface, corosion is integral...

this somewhat deep tech talk has forced me to read along out of curiosity. whew, at first i thought this thread was brainstorming the next revolution in thermal systems for NASA. PC cooling is supposed to be fun too, right? i think some ppl are going about their discussions ineffectively.

if we want to accomplish something as PC cooling engineers, we need to agree to iterate over system requirements. focusing on & modifying requirements results in thoughts like: "let's drop the -40C requirement, we could make 100 -37C systems for $1 instead of 1 -40C system for $100". arriving at system requirements is done in the engineering world by discovering the one design parameter that dominates how well it performs. finding design drivers leads to efficient thoughts like: "forget about pressure for now, it's actually pressure^2/power^3 that gives the most leverage for reducing temps. let's focus on maximizing that first").

obviously more extensive sharing & integration of our knowledge resources would be an improvement, as opposed to having "gurus" argue back & forth with one another over potentially irrelevant issues using random data from unrelated & loosesly controlled experiments. don't get me wrong, i can tell many of you do appreciate the value of controlling & repeating your experiments, but it's hard to use data from a shot in the dark experiment that has little correlation to the engineer's design choice.

arguments in this thread are leading nowhere but to rehash what many of us already know & beat the ignorant over their heads with a hammer?