Cooling fanless radiator, oil submerged psu

I have a question for all u cooling gurus out there, I am building a fanless PC, and wondering what size radiator would be large enough. The system is going to be water cooled, with the following things in my loop: P4 2.8, Radeon 9800pro 128, and my PSU. The PSU is a 300 watt (forgot which brand, its turned a weird way in my comp and i don't feeling moving it.) which will be cooled in a fanless (sort of) way by submerging it *shudder* in mineral oil, leaving all the original fans in it to circulate the oil, then a waterblock to absorb heat from the oil. So the question is, will the 2 square meter surface area of my heatsink be large enough to dissipate all the heat through convection? i'm looking for any estimates you guys may have on temps too. I have a link to the website i'll be getting the heatsink from: Thermaflo heatsinks

They have some graph there that may be helpfull, but I do not understand them. Please help! Any estimates on the power that would have to be dissipated from the system would be helpful.

 

I'm not sure a PSU submerged in oil will work. Given the high capacitances at work in a PSU, the oil would have to be very non-conductive. It would also have to have very low viscosity if you want to have any hope of fans spinning in that stuff. You can forget about Fluid XP+; although it is a low viscosity mineral oil with good heat transfer properties and low conduction, tests have shown that dousing a PSU in the stuff will cause it to short spectacularly. Fluorinert would be a much better candidate but it is expensive and evaporates when warmed, so you'd have to seal the whole lot in an airtight box.

Fans don't like being submerged generally, not even in non-conductive liquids. Adda however makes PC fans that run happily submerged in water (don't ask me why, they just do), and that is what you would have to look at.

As for the rad, that is not hard to work out. A bit of Googling will get you an idea of how many Watts a P4 and a Radeon 9800 radiate in heat. Just add the lot up (and the NB, if you intend to watercool that). Then you need to find a rad that can comfortably displace that passively. If you can't understand the graphs, I suggest you learn. For instance "Heat Sink Temperature Rise Over Ambient" is how much hotter the sink will get than the surrounding room temperature, when it has to radiate a given quantity of Watts. You need to understand what you're building, not just put it together by rote. Use the Search, Luke.

A fanless computer is a nice idea but given the fact that there are many other parts in a PC that get hot (Mosfetts, RAM, drives) you need at least a reasonable breeze flowing through the case. Some slow, silent 120mm fans would be sufficient.

 

zfz - psu
zfz - psu2

zerofanzone

edit:: link

 

Useful links. Although those are not submerged PSUs, they do offer a much better alternative in terms of PSU liquid cooling.

The reason Bladerunner can manage without fans in his PC however is because he has watercooled pretty much everything: Drives, Mosfetts, NB, PSU, I believe even RAM. Unless you make blocks for the more esoteric components and hook it all up to the liquid cooling loop, you really need some fans.

 

For really extreme cooling

check out www.octools.com not sure if that's the right adrees but it is very similar complete immersion liquid nitrogen radiotor colling

 

Not sure, but 2 Square Meters sure is huge for a heatsink!

 

well its so huge because the heatsink covers (will cover) the entire back of my dual monitor, imac style case. although don't get me wrong, i hate apples but they have good styling.

 

Nothing wrong with liking Apples, dude. Without Apple we'd still be stuck with beige boxes (well, except for us modders )...

The octools link is the right address, and they had a system suberged in a basin of Fluorinert cooled via heat exchangers by a bath of liquid nitrogen. Achieved great overclocks, but was not reallly a long-term viable solution...

 

I'd just find a motorcycle radiator or something that is exactly the same size as the right door panel on a case. Loop the PSU, GFX, and VID on it. Passive. THEN run a single 120mm @ 5-7v for an intake.

I am pondering doing this. Just to see if it can be done (it can) but in the sense that "Can I Do It"?

 

I thought of something like that once... A passive rad that is the same size as a side panel. You would swing it out from the computer case like opening the cover of a book (no symbolism there) when switching on the PC.

 

well its going to be a flat case, like the new imac , but it will hopefully have my two flat screens instead of apple's one. The radiator will be the back panel of the computer.

 

I too have thought about this, but you would need a hefty pump for the huge loop . And then the pump might make the most noise in the system too. I'd say use some ducting to suck in outside air and have it exit without staying in the case (pass through)

 

what do you mean a hefty pump, the radiator IS the reservoir !