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How to chose properly your radiators and fan!
Sources: http://www.skinneelabs.com
Useful links:
What are the preliminary requests to ask?
1-What are the components to be cooled?
2-What exist in configuration radiator+ventilator?
3-What is the radiator to choose?
4-Which fan to choose?
5-Finitions? Dust filter naturally!
1-Choice of the components to be cooled
Above all, it is clearly necessary to define the components to be cooled and to identify approximately their thermal enveloppe (TDP: Thermal Design Power).
Let's begin by enumerating the components to be cooled:
CPU: Mother part of the PC on which you can apply a surge, thus yes, naturally it is necessary to cool it.
Northbridge: then there we are at present on a border. The arrival of the chipset P55 which is not really a northbridge. But, beyond that, it is necessary to analyze needs in cooling of northbridge. 2 functions make warm the northbridge: the management of overclocked memory and the management of a multi-GPU. Since you enter into one of these cases (which is to say the your northbridge manage at least one of these 2 functions), it is necessary to think to watercool it.
Memory: it is necessary to watercool it ONLY if you boost it...Otherwise it is not the essential.
Hard disk: useless.
Motherboard: To watercool a motherboard can have three interests. The first one is the silence as certain basic fans make big noise. The second one consists in being able to take up a multi GPU system without suffocating a motherboard by its neighbour. The third reason is that a GPU can go up rather high in tension (90°c in charge in aircooling) and this heat spreads unmistakably in the case, what make overheat the nearby components as the northbridge or even the CPU. To conclude, the GPU is the best choice of components to watercool after the CPU.
On the other hand, the overclocking of the gpu always remains limites because no card accepts a big surge on the chip...Anyway, these three first ones already constitute widely sufficient reasons.
Let's focus now on the TDP of each component:
Above all, it is necessary to be conscious that all components of your system will never work at 100% at THE SAME TIME...Yes maybe certain benchmark (OCCT supply)...So it is necessary to go the ladle for the calculation of the TDP.
PCU: Quad core : 95W (core i5/7 socket 1156) at 150W (core i7 socket 1366), dual core:60W to 100W. Be careful, Intel tends under considered the max TDP of his PCU's. AMD indeed indicates the maximum TDP.
Northbridge: the northbridge have the dimensions of a PCU, so it is necessary to count approximately 50W in full load.
Memory: For the memory, we can say that 2 Go of DDR2 at 1.8V are approximately 40W. A little bit less for the DDR3 at 1.5V.
Motherboard: The top of range for this example. For information, the express PCI standard 2.0 imposes a maximal electric consumption of 300W by card. The thermal envelope being slightly lower physically than the electric consumption, we can consider that the TDP is about equal to the electric consumption ( the distance is compensated with the cooling of the memories and mofset for example). For example, a GTX285 consumes 189W in load 100% and a GTX295 289W...here are good estimations...:)
Pump: the pump always warm the liquid. Let's count 18W for a MCP355 or 20W for a MCP655.
Example: let's imagine the following configuration to watercool:
Core i7 920@4GHz (1.35v) : 150W+70W
Chipset X58 : 50W
3-way de 3xGTX285 1Go : 579W
It gives a maximal , theoretical total of 849W...value purely theoretical ceiling which will never be affected in reality, for lack of real application which loads so much the machine.
USEFUL CRAFTINESS: How to easily find the thermal envelope of one's current PC? Until now, I presented you rather theoretical values, finally enough far from a daily use.
However it exists a simple method to know the maximum thermal envelope of the PC. Here is the method:
1-Buying a small wattmeter of socket. It costs 10 Euros at the supermarket/ At the do-it-yourself shop.
2-Launching your favorite applications and observing the electric power consumed in the grip.
3-Documenting the return of your supply (between 70% and 87%).
4-Multiplying your power consumed by the return on your supply and you will obtain the maximal envelope of your PC.
Example: Core i7 920@4GHz (1.35v)+X58+3-way SLI of GTX285 (not OC): under Crysis, I obtain a consumption of 700 w. My supply, a HX-1000...I look at the return with regard to the consumption.
I take 86%.
Thus I multiply my power consumed by the effective return and it gives: 700*0.86=602
This value calculated empirically represents the practical maximum of the thermal waste, by counting ALL the components of your PC (except supply)...and moreover, I ignore the return of the electric power consumed/ thermal power but this one is maximum 1 and a chip is not either dedicated to heat...:)
Mini-conclusion: empirical thermal return (602W any PC) vs Thermal (849W CPU+NB+GPU)
What is necessary to retain is that between the theory and the reality, it exists a difference really important! All this to remind that you should not give in to the temptation to oversize the watercooling.
Let's pass now to the second part...;)
2-Configurations of Radiator + Fan
Before seeing where you could implant, it is necessary to present the different possible configurations of fans or arch which allow to optimize the airflow.
This article allows to review very easily:
http://martin.skinneelabs.com/Radiator-Fan-Orientation-And-Shroud-Testing-Review.html
Here is the final classification:
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Several elements to be retained (Only to my opinion...;)):
1-The best configuration in terms of relationship between space/performance is a simple push.
2-Radiators shroud are not worth because on their place, we can put a more effective pull
3-In low speed of fan (1350 rpm), it is better to have a system in pull and in high speed
Now that we know it, it is possible to pass on the choice of radiators..:)
3-Which radiator?
Before beginning, let's remind the basic principle of a radiator. This last one has for objective to offer most large surface between the liquid and air. To do so, the radiator is made of a big system of folding/maze/labyrinth (maze)
