I can't speak for BillA, but let me refer you to this article by myv65. Specifically, check out pages 3 and 4 (it's a very long read). I can vouge for the accuracy/truth in this article, I have verified the information.

That should clear up the Al vs Cu question.

(PS: I still believe that Aluminium is good for a waterblock: it may not be the best in performance, but it will provide anyone with a cheap ability to watercool their rigs, albeit at the cost of a large overclock):cool:

thanx, i saw that above but i had to argue bill and forgot:p

did anyone even see my post?
Tokamac

yes i did see your post, and i kinda responded to a few at once... yes its pretty much 2x more conductive...in theory pretty much, but when it comes to real life situations of watercooling computers its not exactly like that

It's statements like your last one that bring exasperation to engineers. Metals have no brain. They do not know if they are cooling a CPU, being used to conduct electricity, or even sitting in the ground in varied states. Pure copper will always behave the same in conduction. Pure aluminum will always behave the same in conduction.

Pure copper will always have nearly twice the heat conductivity coefficient of aluminum. This means that in equal shapes, copper will always have slightly more than 1/2 the temperature differential as aluminum when conducting heat through the same pathway.

Why you will not see a precise difference for a given power is that the flow pathway of the heat will not be precisely the same for the two materials. Copper will cause heat to spread over a larger area than aluminum, all other things being constant. For this reason, you will frequently see differentials less than 1/2 for copper versus aluminum.

In air cooled heat sinks, you'll actually find that aluminum does a better job as fins/pins. Not because of some absurd idea that "aluminum gets rid of heat better than copper". It's simply a question of surface area. For a given weight, aluminum has far more surface area and gains the advantage in convection. I'll guarantee you that less than 5% of the people that consider themselves cooling gurus really understand this basic priciple.

In water cooled blocks, this advantage is largely muted because of the inherently higher convection coefficients of water. This puts an even higher premium on a material's conductivity.

Now, as BigBen2k and BillA noted, you can do just fine with aluminum, but you'll never do as well as copper. I'll guarantee that you'll tend to see a variation of 2-5°C for most blocks and power levels if you made the blocks from both materials. Is the extra cost of the raw material and machining difficulty worth 2-5°C? Not for most people, but that doesn't change the fact that it exists.

What you see as an irate attitude towards your questions folks like BillA see as ignorance in search of an easy answer. All the answers you seek are available, but it doesn't do a whole lotta good to simply tell you the answers. Unless you understand why things are the way they are, you doom yourself to blindly proceeding randomly. You may make a few different blocks with some performing better than others and have no idea why. Rather than pop in and ask for all the answers, invest some time to search for those answers on your own, both through hands on research and by reading. And I got news for ya, if you think you're going to find good information cruising forums you are sadly mistaken. There are plenty of very smart people that hang here and elsewhere, but they're outnumbered by morons that spout conjecture without proof. Again, unless you understand the real issues, you have no way to separate the good stuff from the garbage.

OK, I'll get off my soapbox now. . .

actually that want the origional point of this thread, the origional point of the thread was: would you buy aluminum blocks? would you refrain from buying the block just because it is aluminum and would yield 2-5c dif from copper?

quote from my origional message

OK, getting back to your original point. The obvious answer is that some people will and some people will not. It is also only one of the factors involved with deciding on a block. IMHO, there are far more factors to consider such as fittings, channel configuration, hold-down mechanism, company (or individual) reputation, cost, appropriateness to remaining system components, etc.

I'll tell ya who I wouldn't buy from. Someone that has no experience. Someone that doesn't exhibit a grasp on what separates a good block from a bad one. Someone that is fly-by-night and may not be around to help with problems. Someone that hasn't done their homework to develop a good block. The list goes on and on.

I guess that leaves only people that I know very well from forums AND can make blocks (this is a very, very short list) and the "big names". Even among the big names, I wouldn't buy from quite a few simply because they don't seem to know much about what they're doing either. Some seem to think it's enough to make a pretty block. OK, nothing inherently wrong with that as lots of people are more concerned with how their system looks through an acrylic window than how well it actually performs. That does not describe me, however.

There's all kinds of people out here that buy blocks for all kinds of different reasons. Many (most) couldn't tell you the difference between a "good" block and a "bad" block. With a portion of the buying public clueless about what matters, selling on looks alone has merit.

Anyway, aluminum and copper is but a small part of the equation. Develop a block that performs well, mounts well, and looks good. Show it off and support your customers. Do all this and you'd be on your way. Easily said, but tougher to execute.

i know exactly what your saying, i dont have much of a reputation here but over at overclockers and wc101.com i have a pretty good one, iv made somewere areound 8 blocks and that is a small number compared to the amount i would have made if i had the monies for mill and material, im here all the time to help out, iv done tons of homework, thats were i have decided on aluminum, for many reasons in above comments, have you seen any of my blocks???

Quote:

I guess that leaves only people that I know very well from forums AND can make blocks (this is a very, very short list) and the "big names". Even among the big names, I wouldn't buy from quite a few simply because they don't seem to know much about what they're doing either. Some seem to think it's enough to make a pretty block. OK, nothing inherently wrong with that as lots of people are more concerned with how their system looks through an acrylic window than how well it actually performs. That does not describe me, however.

pretty blocks suck, iv made a few but its pointless im a function over form for watercooling, all my previous blocks(previus to the 2 solid acrylic with copper based blocks iv made were 100% soldered, the fittings were even soldered in, check out the gallery and waterblocks section in wc101.com forums, youll see 2 of my blocks, and in my avatar a few more... i also dont think that how it looks shoudl be paid attention over how it performs, although i do like to color my water etc :D

[quote
There's all kinds of people out here that buy blocks for all kinds of different reasons. Many (most) couldn't tell you the difference between a "good" block and a "bad" block. With a portion of the buying public clueless about what matters, selling on looks alone has merit.

Anyway, aluminum and copper is but a small part of the equation. Develop a block that performs well, mounts well, and looks good. Show it off and support your customers. Do all this and you'd be on your way. Easily said, but tougher to execute. [/quote]

this is my plan to make a good block and have great support, and make the good block aluminum is one of the things i wanna acomplish, i have another design cadded up that i mite take to the cnc at school if i can get access again(most likely)
my first kit that im building for someone is almost complete, waiting for the pump, and just to mod the intake and make it all fail safe,
theres a pic of a few parts of it leak testing, the h/c shroud (fan not included) and the waterblock 100% soldered together 1/2 barbs and clearflex 60 tubing(only 1 small segment of scrap shown)

-edit- the main reason i made those acrylic ones is becuause i was running out of material and didnt have cash for more and had scrap acrylic laying around i made use of....

I don't know about you myv65, but I'm the type of customer that wants to experiment with block designs, yet I don't have the facility to produce one, so if MaskedGeek is offering, I might very well take him up on it.

I think you might have misconstrued MaskedGeek's purpose here: beyond the Al vs Cu theory, there is a business aspect, and what I see is that Jon (MaskedGeek) is doing some market research, to get an idea of the number and type of customers who would go for Aluminium blocks. He's already outlined his business plan, which is to produce Al blocks, and he's going to redirect the profits to acquire the necessary tools to produce Copper blocks.

It all sounds good to me!

Jon, if it's of any interest, I might go for an acrylic prototype, so that I can test flow paths, and look into milling challenges. The block wouldn't be of any use otherwise.

yeah i have done 2 designs in acrylic, it kinda sucks to machine tho, it melts and gives off fumes, im gonna try to get ahold of some poly sometime...

im glad someone is understanding me and is able to explain it better than i can:)

Some performance predictions based on "my best fit model" for your Swiftech 462u data presented here http://forums.procooling.com/vbb/sho...5&pagenumber=8. Used a T/W value obtained by allowing 0.05 c/w of the TIM(C/W) for the offset of the die tc.
Best fit calculated assumming the turbulence created in a 6x6mm square entry nozzle is maintained over all the wb base. From the Reynolds number calculating the Convection Coeff (Sieder-Tate) and then adjusting the effective Convection area. :
http://www.jr001b4751.pwp.blueyonder.../ConvAreaa.jpg

The "best fit 80x80mm" .is larger than the internal base area but.............

Showing the predicted effect at diiferent flow rates of Cu and Al bp thickness and the change to the new smaller AMD (80sq mm ) die .

http://www.jr001b4751.pwp.blueyonder.co.uk/CuAL8mma.jpg
http://www.jr001b4751.pwp.blueyonder.co.uk/CuAl3mma.jpg
http://www.jr001b4751.pwp.blueyonder...CuAlThicka.jpg http://www.jr001b4751.pwp.blueyonder...uAlThickNa.jpg


Edit: Added C/W v Thickness curves for 8x10mm Die

interesting numbers Les, the smaller die is going to make things hotter for sure
my take on the geek's lament ?

aluminum = the cheap 'solution' that doesn't work as well

save a buck and add some heat

"beware he's grumpy" really? i couldnt tell?:rolleyes:
im not even gonna say any more...

maskedgeek

what is the topic of this thread ?

you seem displeased that you cannot sustain a chorus of "aluminum is 'just as good' as copper"

you as a wannabe fabricator may prefer aluminum for various reasons,
but ultimately they all relate to lower cost

and such paths, predictably, also lead to lower performance

no biggie
no individual is 'winning' anything, we're discussing material properties
- if YOU want to ‘talk technical’ you had better start becoming comfortable with numbers, lots of them

"Need suggestions Copper or Aluminum"

FINALLY you start making sence!!!

partially the reason i want aluminum is the tools i have to work with, the cost isnt a biggy, but the labor of working aluminum vs copper, have you ever done any copper and aluminum milling and whatnots? it takes experience to know these things,

I plan on using hi quality designs and blocks in aluminum, itll only be around 2-5c lower than it would be with copper, does 2-5c really matter? toward the 5c it may but 2c is no big deal...

I had to quote that line twice.

Yes, I would pass over a product that runs 2C (never mind 5C) hotter than the next one. I'd pay top dollar to better what I have by 2C, and I have proven that time, and time again. The line of heatsinks, and waterblocks on my shelf is my proof.

Aside from that, look up #Rotor... he makes two versions of his block, one copper, and one aluminum...same design.

(hmmm, his site appears to be down...)

ok thanx for the comment, im glad i see some truth here, iv seen rotors stuff, but never seen his aluminum blocks, how do they compare to his copper ones?

I can't comment on the difference...I never inquired about the aluminum block when I bought mine (Cu)...we did talk about battery effect, but that was it.

Come to think of it though, here's a guy that has a few systems running on one water loop...one being a dually, and he's using his copper blocks on them.

IMO, he wouldn't use 2nd best (and more expensive) when he has both at his disposal. Would he?;)

Interesting indeed...

because it shows that copper is best at at least 10mm bp thickness, for most flow rates, where Aluminium is best at 10mm OR LESS, for flow rates above 3 gpm (180 gph).

I don't believe that the performance difference is worth all the bashing that ya'll are giving MaskedGeek here. Aluminium has its place, just not for serious overclocking. A Mercedes is better than a Lada, no one can deny that.

Perhaps a better analogy would be to a Honda - not flashy, probably won't win any street races, but will get you where you are going economically and reliably.:D

Bob

come on bigben2k, pull it together

a lower T/W (like "C/W") is better
take another gander at those graphs, apples to apples eh ?

when maskedgeek stops making assertions that he cannot substantiate
"a good waterblock will perform the same in Aluminum as in Copper.... " (in his initial post)
then he won't get banged on

he has this same thread on a number of forums where he's singing the same song
- this is the only place I'm telling him how ignorant he is
(as have others - but he hears only that portion convenient)

BillA: The way I see it, I agree that MaskedGeek has some misconceptions, and that he doesn't have accurate enough data/testing to prove that Alu would perform at par with Copper. I know better, you know better, and I would think that most people know better too.

The point is that Alu does have its place. It's not useless, it's not a waste of time and/or money, but there is a disadvantage, in that it will *never* perform as well at Copper, it's just theoretically impossible, and as testing would show, the truth.

I'm glad that you're not following him everywhere to put him down.

Anyways, this thread should get back on topic. Now that we know the truth about Al vs Cu, would anyone be willing to buy an Aluminium waterblock, knowing that its purpose is to get you watercooled, so that your computer can run quietly, but with the understanding that it will not give you the ability to overclock your computer nearly as well as a Copper block?

Well, I would like to answer the question in two ways. First, I would not buy an aluminum waterblock on a high-end CPU. On a cooler CPU with less wattage (such as a small multimedia box like the Shuttle SS51) I might buy aluminum. It depends upon the price differential and also on the maintenance differential. If Aluminum is 1/2 the price.... OK. If Aluminum is much easier to maintain (because you don't have to change the water as often because of less galvanic corrosion), then yes.

Having said that, I would like to follow up by saying that I made my first three waterblocks in aluminum. First, I got the aluminum for free (scrap from the machine shop here at work). Second, I don't know how to machine very well and aluminum is MUCH more forgiving. If you are doing it yourself, learn on aluminum, then join the big boys. :D

Maybe when I get some free time I'll make my own copper waterblock. Too many pots on the stove right now. I certainly won't buy one if I can make it though, and I could.

As for making it a consumer product, unless you can show a considerable price differential (and I don't believe you can), stick with copper. Watercooling hobbyists are performance junkies and second-rate solutions just won't fly.

You've got to ask yourself who is going for watercooling in the first place, and the answer is performance crowd looking to get the most out of cpu, and believe me because I'm not just designing block, I'm crazy about overclocking too, and I know that even 1 degree can make a difference geting theat few more MHz, also I just cant see how you would cool new t-bred with its 84mm2 of surface area overvoltage and overclocked, Al just can't spread heat quickly enough to larger area, so you would need to compensate that with very fast flow, with those cpu-s the difference would be a lot bigger then 2-5 degrees. I can't say that from real test but if I just make few simple calculations, the difference between copper and Al is very noticable.
So I see the main problem with Al , that it just can't handle very small cpu cores, It would be good for northbridges and gpu-s where all those chips are bigger and you have foot print of the block the same size as the chip so you can have very thin base thickness for very good cooling.

i see were yoru comming from on the small dies... but still from tests iv seen aluminum blocks do the same or a LITTLE less than copper, like webmedics crystal coolers, he did silver inlayed copper copper copper inlayed aluminum and aluminum and he says they all perform the same...

I think that some people turn to watercooling for the quiet aspect, but I'll agree, there's probably fewer of those.

ok guys as of now im gonna use aluminum and if i see a substansial(spelling?) diff between aluminum and copper ill switch over or do everything but cpu blocks in aluminum and use corosion inhibitors.....

Better use anodization, that way you can have some nice colored block that will appeal, and forget about that galvanic corrosion

yeah thats exactly what im thinking, black :cool: and the corosion i saw my corosion i did to a popcan block with no corosion inhibitors, it wasnt bad but it looked like salt build up for some reason, so anodizing it will stop corosion rite? and if i build a complete system all aluminum i wont have corosion rite?

Yes, and yes of course