Hasn't there been a lot of news about Graphene? Silicon still works for the current designs.
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p of nickel: 8.902 g/cm^3
p of copper: 8.940 g/cm^3
p = m/V
V = m/p
V = 790 g / 8.902 cm^3 = 88.744 cm^3
m = 88.744 cm^3 * 8.940 g/cm^3 = 793.37 g or 0.793 kg :shrug:
Also remember the difference between heat, thermal energy, and temperature. Heat is the transfer of thermal energy. The hotter something feels the more thermal energy it is transferring.
So first we have to ask ourselves what we're transferring the thermal energy to. It turns out that air has a terrible specific heat and has trouble absorbing the energy fast enough causing a build up of average thermal energy, or temperature. We constantly need to be pushing the air that has already reached or is nearing the average temperature of the system out of the way. The greater the temperature difference between the air and the heatsink the faster the transfer of thermal energy.
Comparing copper to aluminum is tricky. Copper may not be able to dissipate the thermal energy as fast as aluminum, but because it has a higher specific heat it can contain and absorb the energy at a higher rate. From what I understand aluminum cannot contain thermal energy worth crap. If you heat up one end of an aluminum rod the other end will have a significant temperature difference. This is why if you remove something on an aluminum sheet from an oven at 450 degrees you can immediately touch the sheet. Copper on the other hand is great at containing and transferring the energy but is not so great at getting rid of it. This is why heatsink manufacturers us copper to transfer the energy and aluminum to dissipate it.
So if aluminum heat pipes were used you'd end up with less energy transfer away from the origin and because the air can't absorb the concentrated energy efficiently you'll end up with a higher average thermal energy at the origin, or high temp CPU.
With the all copper TRUE the thermal energy will be able to disperse more evenly to the far corners of the heatsink, however in theory without aluminum's inability to contain the energy, despite this all copper monstrosity's ability to contain more energy it should result in a higher temperature.
Utterly ridiculous. Really, did no one study heat transfer? So what if it's heat capacity is greater, it means it can handle greater heat loads, it doesn't mean it "holds onto heat more tightly"...Like I said before, with higher surface temperature comes the added benefit of increased temperature gradient with the ambient air, which directly INCREASES the convective heat transfer rate.
Sure The copper sink will be warmer, because the rate of heat transfer to/through it is greater, and because it can store more energy, but that energy will never be greater than the thermal source because of the temperature gradient that will exist with the bulk air. Who taught you guys this stuff?
You have a source to back that up?Quote:
This is why heatsink manufacturers us copper to transfer the energy and aluminum to dissipate it.
here's a sweet and short discussion on the matter, because I can't seem to get the point across.
http://www.jonnyguru.com/forums/showthread.php?p=43184
Marketing has gotten you to absorb the 'copper for transfer, al to dissipate.'
The correct statement should be aluminum used for more cost effective heat transfer.
And I think baron_davis has a point, ryboto. Over time the copper will equilibrate with a higher TEMPERATURE given constant input of heat. Heat != temperature.
Also, ha! That thread was mine : )
I'll consider it if it will work with x58. Looks like the kind of heatsink I want next.
Transfer IS dissipation. Dissipation IS transfer. Right?
Stainless steel is less dense than pure copper.
Graphite is not suitable for semiconductor. graphene is, they are essentially the same, but the technology is not there yet.
if the entire true was made out of alu and that was swithed with copper, it would weigh approx 2622g. But since it is part copper part alu it cant be measurred that way.
The nickelplating is very thin and won't mean much for the equation.
The copper itself might be warmer, but that's only because it's conducting heat faster. Look at the equations
1.) conduction through heatsink from heat source
Q1= K*A*(T1-T2)
where Q1 is the heat load, or rate of heat(watts from a CPU), K is the thermal conductivity, A is the interfacial surface area, T1 and T2 are the heat source temp and heat exchanger temp resepctively.
2.) Convective heat transfer from heat exchanger to air
Q2 = h*A*(T2-Ta)
where h is the convective heat transfer coefficient of the fluid(air in this case), and Ta is the bulk temperature of the fluid(air). Heat transfer to the air is dependent on the properties of the air(temp/velocity/h), and the temperature gradient between the exchanger and air.
If we had two heatsinks of the same design, the only difference being their material of construction, Al vs Cu, the number we change in equation 1 is K. T1 and T2 will be different for Al vs Cu. The base temp, T1 will be lower, T2 will be greater, meaning a lower CPU temp. In Eq. 2, the heat transfer is highly dependent on the temperature difference, if T2 is greater, the heat transfer to the air will increase.
The only variable changed between the two is K, the heat transfer is determined based on the conductivities, therefore Copper is the better choice.
In short, conductivity is dependent on the material of the heatsink, heat transfer(or dissipation) to the air is dependent on the properties of the bulk air.
I do fully apologize. I'm looking at a text that contains the specific heat and heat transfer coefficients of several materials. It shows aluminum with a lower specific heat and higher heat transfer coefficient. It turns out it's a misprint. The decimal is in the wrong place on the aluminum's coefficient.
Well what I said would be true given aluminum could dissipate heat 10 times what it actually does. :p:
That thing would have to be solid copper to weigh 6.6lbs (3kg). It might weigh 1lb.
Don't you guys get it? The prettier the material, the better it cools!
Diamonds are a girl's best friend > silver friendship ring > copper ankle bracelet
My head was about to explode when people were saying that Aluminum would be better at getting rid of heat than Copper.
I was just reading thru this thread and I've come to a few conclusions:
1) Lots of people like to argue any point at all just for the sake of arguing!
2)A great many of you people are a hell of a lot smarter than I am.
3) I always thought copper was used for the base and alum used for the fins as copper transferred heat faster but aluminum dispersed the heat faster.
That's what I think not know and reading here I may well be wrong.
4) Pretty looking heatsink.
5) We'll find out how effective it is when someone here tests it and not before.
:up:
It'll probably be effective, just how effective over the original version is questionable, since think aluminum fins are probably pretty effective as is..
Man, that $99 is looking attractive as a good start for a watercooling loop instead.
a 99 dollars watercooling loop (new, not used parts) are almost equal or it could be wrost than the thermalright ultra 120 extreme. besides, not everyone will want to go through the hassels of watercooling and worrying about their loop whether is leaking or not. On the other hand, air cooling is way faster and easier to mount or disassemble.
3 pounds, you mean? 3KG is almost 3 times as heavy as some of the largest heatsinks out there. Even this 10-heatpipe http://xtreview.com/images/scythe%20...1000)%2004.jpg weights only 1.1 KG, and is *by far* the biggest CPU heatsink ever made.