Reflections on watercooling: Difference between revisions
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* Neither air- nor water-based cooling can get your temperatures below ambient (this can be achieved with phase cooling, thermoelectric aka Peltier, and cyrogenics). If it's 30 degrees in your room, your coolant and component temps are going to be at least 30 degrees. <b>It is useless to report temperatures without reporting ambient temps.</b> The effectiveness of your cooling system is measured by how close it gets to ambient, ΔT. Likewise, your heat-generating components are going to be hotter than your coolant. | * Neither air- nor water-based cooling can get your temperatures below ambient (this can be achieved with phase cooling, thermoelectric aka Peltier, and cyrogenics). If it's 30 degrees in your room, your coolant and component temps are going to be at least 30 degrees. <b>It is useless to report temperatures without reporting ambient temps.</b> The effectiveness of your cooling system is measured by how close it gets to ambient, ΔT. Likewise, your heat-generating components are going to be hotter than your coolant. | ||
* <b>The goal is to move heat from the heat-generating components, and ultimately from the case.</b> Effectively moving heat requires (a) thermal conductivity, (b) contact area and (c) a temperature gradient. The thermal conductivity of air is about two orders of magnitude less than water, which is about two orders of magnitude less than aluminum or copper. | * <b>The goal is to move heat from the heat-generating components, and ultimately from the case.</b> If you can't remove as much heat as you generate, temperatures will rise with time. If you can remove all the heat you generate, temperatures will fall towards ambient. Effectively moving heat requires (a) thermal conductivity, (b) contact area and (c) a temperature gradient. The thermal conductivity of air is about two orders of magnitude less than water, which is about two orders of magnitude less than aluminum or copper. | ||
** A processor without a heatsink is depositing heat directly to stagnant air, which will heat up (reducing the temperature gradient) and can't take much heat anyway. | ** A processor without a heatsink is depositing heat directly to stagnant air, which will heat up (reducing the temperature gradient) and can't take much heat anyway. | ||
** Adding a heatsink means the heat is deposited into a good conductor with more surface area...which in turn deposits into stagnant air. This air will heat up, and eventually the heatsink will, as well. | ** Adding a heatsink means the heat is deposited into a good conductor with more surface area...which in turn deposits into stagnant air. This air will heat up, and eventually the heatsink will, as well. | ||