To Jon: You guys did a GREAT job. I decided to do this because of YOUR video. It's definitely over the top, and that's why I wanted to do it. It's also extremely effective at silencing the high-speed mobo and GPU fans.
To xan: smart ass!
To wim: I have seen posts/pages showing submerged PSUs, but in this case I didn't want to add the PSU's heat output to the oil. I have a Zalman 850W PSU that has a 140mm fan. It's very efficient and very quiet (but not silent) in open air.
To bruce: I'm having mechanical issues, too. It's not my strong suit. I just sat the mobo and gcard in the oil without any mechanical support -- not a good final solution. I'm still thinking about how best to support the cards, and how to physically organize the whole thing.
I have a double-hull setup: a 5.5 gallon aquarium placed within a 10 gallon aquarium. Initially, I did this because I didn't completely trust the cheap 5.5 gallon aquarium, and I wanted a backup container. More on this later.
The length (front-to-back) of the motherboard is about a half inch shorter than the depth of the aquarium, which is perfect. I attached the mobo to a sheet of plexiglass (1/4" thick, I think) which is about 6 inches longer than the mobo. I put a GPU into a PCIE slot, and dropped the whole thing into the tank. That extra 6 inches of plexiglass gives me something to hold onto when I pull the mobo out for servicing (which I haven't done since filling the tank - I'm not looking forward to that).
The GPU card is supported only by the PCIE connector. I know this is bad. I need to get a proper frame for the mobo and GPU.
I left all the fans on the mobo and GPU. They spin just fine in the oil -- just slower. I'm sure there is a cooling benefit as they churn the oil and mix the hot stuff around the tank. There's two fans on the mobo, one on the CPU, and one on the GPU.
The inner tank (5.5 gallons) sits within the outer tank (10 gallons), lifted two inches by sections of 2" diameter PVC pipe. Initially this double-hull was for safety (ever try cleaning up 5 gallons of spilled mineral oil? No? Me neither, and I aim to keep it that way!). But now I'm thinking the outer tank can help with the cooling.
Currently, the outer tank holds only air. This is bad. It's acting as an insulator, because the air isn't moving around much, and is slowing down transmission of heat energy to the room. I think my next step is to fill it with water.
That will make 5 gallons of mineral oil and 5 gallons of water. Since water has 2.5 times the heat capacity of mineral oil, I'll be more than tripling the thermal mass of the system, which means it will take over 3x the heat energy to achieve a given increase in temperature.
Furthermore, instead of having a layer of immobile air surrounding the inner tank, it will be water, which conducts heat much better. The insulating effect will be gone, and the whole shebang should be able to shed heat (albeit passively) much more effectively.
As for active cooling -- I may experiment with ice packs or water chillers for the outer shell. I'm just playing around with this, after all. I won't pretend any of this is practical.
I'll see if I can get photos of this - I realize it is hard visualize what I'm describing.
Anyway, this system is a midrange CPU and midrange GPU sitting on a high end mobo. Front side bus is pretty fast with
[email protected]. Honestly, I don't know if this system pulls much juice or not. But even when it is just idling, the oil gets HOT! Looks like the oil has taken about 8 hours to get close to 120F, with the system thermometers reporting 118F for the CPU, 127F for the system, and 144F for the GPU. The system is just idling, showing only the desktops. No graphics, and CPU meter shows 0%.
I would consider this a dismal failure, but I still have that outer tank holding (very warm) air, acting as an insulator.
I'm going to run a few torture tests on the system, record the stable temps, and then see what happens when the outer tank is filled with water. I really do expect that to help, although I don't know by how much.
-stefan