That's what I'm thinking makes the difference. Basically the water works as a heat reservoir, absorbing more heat energy. I guess as it heats up, the speed at which heat is lost to ambient increases, offsetting the decrease in heat absorbtion from the chips. I'm sure there's all sorts of numbers that can be crunched to explain what happens.
But if so, surely the size of the reservoir is important? This reminds me of the oil-bath PC that Al linked to a while back. That cooled passively, using the whole surface area of the PC to disipate heat from the oil. My ill-informed gut feeling is that you need a decent amount of water for it to work.
Not particularly Shifty. Well, you're partially correct, but he'll be seeing lower operating temperatures of the core with water because of two other things at play:
- His water is only sensible heating/cooling withing a particular (low temperature) range.
- Because he likely has a whopping great powerful pump blasting water around the circuit at a high flow rate.
Basically, a high flow rate around the circuit can negate the fact that sensibly heated/cooled water is a shitty transport medium (but not as bad as air). But to get better performance in a system you need a powerful pump to get the water flows up so high, and as Alstrong succinctly put it, a massive amount of surface area on the air side to remove the heat at the other end. The larger your flow rate, the bigger the pump needs to be, and the more surface area you need in your radiator as your water will spend less time in the radiator section of the circuit for a given volume of the stuff.
It would be impossible for him to run the same system in a console the same way, because there's no way the console power supply could take the load on the pump, nor could the radiator or pump unit itself be contained within the console.
Water cooling in a console is a pipe dream.
Also, if I understood your suggestion of a system filled with fluid shifty? I suppose that such a system could be possible, however at the external fluid/air interface how would you remove the heat without some kind of high surface area radiator? And without something to provide circulation of the fluid, your fluid would simply remain static in the system, and once the overall bulk fluid temperature has risen to the same temperature of the core, without fluid circulation through your radiator, you have too poor heat transfer there to be able to get the heat out of the system. Only way I can see something like that working is if you had some kind of external heat exchanger connected to the shell of the console, and a pump driving the fluid through it. That or a completely self contained thermosyphoning system that takes advantage of natural convection currents to drive the fluid around a loop, but then say hello to colossal consoles and core operating temperatures in the 100-250deg range (as the temperature of the fluid needs to reach a specifically low enough density for it to work).