Watercooling Question

[dyingstar]

Hey Guys,

I have seen alot of sites that say watercooling is way more efficient than air cooling. This would make sense, considering water conducts heat more efficiently than air.

But here's my question: since water cooling and air cooling both must use a radiator-type device to release heat energy to the AIR, wouldn't they have save effectiveness? The processor in a watercooling would have cooler temps at first, until all the water in the system heated up to a temperature dictated by the heat dissipation rate of the radiator.

As I see it, the increased effectiveness of watercooling lies more in the fact that larger radiators can be constructed because the radiator is not hanging directly on the mobo.

Am I missing something obvious, or does this idea make sense?

[tybrenis]

Yep. You're right. It all comes down to how much heat your radiator can remove. However, you can't exactly put a huge radiator right over your processor, now can you? However you're correct about the water temp being reliant on the radiator. Thats why I'm building a peltier cooled system.... =D

[dyingstar]

Since you mentioned peltiers, I have a question about those too. All the peltier waterblocks I have found on the market are 150+ (USD). I can buy a 2x 2 x .5 inch block of copper for 10 bucks and a pelt for 30. However, I have no precision cutting tools to give an extremely flat surface for the block.

So my question is, how much difference would a extremely flat surface, compared to a just any flat surface make in the performance of the waterblock?

[jdbnsn]

I don't think there is any way to answer that with precision, but if you think about the concept it could make a huge difference based on how irregular the surface is. If you have a perfectly flat/smooth surface between the block and CPU then you theoretically have 100% contact, but if you have tiny saw-tooth grooves in the surface, only the tips of the ridges will be in contact and able to transfer heat, tips may only give you 5-10% contact. Of course thermal paste can help fill in these inperfections but with reduced efficiency. You can probably get away with it and have decent heat transfer but I would do your best to get as close to 100% contact as you can.