Water cooling question

[Dogbert]

Is it possible to create a small passive yet efficient water cooled system ?

The idea is to have an unvented radiator above the heat sources so cold water from the radiator will replace the hot water inside the computer naturally.
I'm not talking about an overclocker's system here, just an looking for an idea as efficient as the generic oem stuff yet 100% silent. I know it should be possible with a huge radiator, but can it be achieved with a small one as well ?

[Greebe]

Yes it's possible, but very ineffecient. Reason being it takes pressure (heating) to make the water flow and as a result must operate at higher temps todo.

There is such a product on the market believe is sold in Japan, but never caught on because of it's limitations, which include the above, it's mounting orientation is critical to operation and cost.

[Dogbert]

Thanks for the info !