additional questions:
- are bigger heat sinks also better heat absorbers?
- how come the heat sinks are not flat, what are the prong tops for? is there a reason why they are shaped that way?
- what is the melting point of CPU heat sinks?
2007-05-18 00:19:17 · 0 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
The heat sinks are usually made from aluminum and the prongs are there to get more surface area for heat transfer and they absorb as well as radiate.
2007-05-18 00:22:37 · answer #1 · answered by Gene 7 · 1⤊ 0⤋
Heat sinks are usually made from metal, because metals have high thermal conductivity. Some of the best are gold, copper and aluminum. Given that aluminum is the least expensive and light weight it is the most common.
Heat sink is probably not the most correct term for the thing on your CPU, heat convector is more appropriate. A true heat sink can keep things cool by absorbing the heat, for example the earth is a good heat sink because of its massiveness, you can pump lots of heat into it but you won't heat up the earth.
What your CPU 'Heat Sink' actually does is transfer the heat from your CPU into the surrounding air. This process is called convection - Heat may be transferred in 3 ways: Convection, Conduction, and Radiation. Convection is heat moved by a fluid/gas, Conduction is heat transmitted through a solid, and radiation is heat transmitted by electromagnetic waves (infrared - i.e. like what you feel from the sun).
So in your CPU 'heat sink' first the heat is conducted from the CPU into the heat sink, then it is convected into the air. Now convection is dependent on the surface area in contact with the air, more surface area = more convection, that explains the prongs, they provide more surface area than a flat surface, same goes for the fins on motorcycle or lawnmower engines, and why your car radiator has lots of small flat tubes instead of one big one.
In addition to surface area, convection is increased with the speed of the fluid moving over the surface - hence most heat sinks have a fan. Its the same reason why we have a 'wind chill factor' - cold air blowing on you hard 'feels' much colder because it is sucking heat out of your body faster than still air.
Finally, the melting point of pure aluminum is 660 C (1221 F), often aluminum is mixed with other metals to form an alloy for improved properties, if so it effects the melting point a little bit, but not that much.
2007-05-18 04:16:04 · answer #2 · answered by Leonardo D 3 · 2⤊ 0⤋
Aluminium is the usual material, because it is light, cheap and conducts heat extremely well.
Other things being equal, a bigger heat sink will always keep things cooler.
The prongs are there to increase the surface area of the heatsink. They are needed because you are mainly relying on air to carry the heat away and the bigger the surface the more air is in contact with the heatsink.
The melting point of aluminium is 660.32 °C but your CPU will be destroyed long before it reaches that temperature!
2007-05-18 00:38:57 · answer #3 · answered by rrabbit 4 · 1⤊ 0⤋
If it worked good before you most likely just have to clean all the dust out of the tower. Dust insulates and does not allow heat to escape. Clean it up inside and I am sure all will be fine. Take extra care cleaning the heatsink, but clean it thoroughly.
2016-03-15 02:10:01 · answer #4 · answered by Anonymous · 0⤊ 0⤋
as they said Aluminium , it conducts heat extremely well. and it cools faster then other material
2007-05-18 01:43:42 · answer #5 · answered by Red Snow 2 · 1⤊ 0⤋
Most of them are aluminum.
2007-05-18 00:24:47 · answer #6 · answered by zbalat 7 · 1⤊ 0⤋