Nothing new about mineral oil cooling computers. You dont even have to submerge the components to take advantage of the cooling effect. You just have to have it flow over top of what you are cooling.
Is someone planning to mineral oil cool a HEX4M?
That would not be sensible, the only advantage of mineral oil cooling is that you don't need to make cooler blocks, you can stick whole board in because oil remains non conductive. I think most people do it for gimmick aesthetic reasons ( fish tank setup with lights etc )
With constant 400W for each board you would need a large oil volume or you would need to employ a radiator/fan/pump setup and so are back into plumbing, may as well employ blocks then and just use water.
Actually, your wrong. First off you still want a block to make the heat dissipation larger.
Second a pump aint shit, just move the fluid consistently.
A car radiator with an adequate fan can more efficiently cool. If the shroud is setup right. It can easily run in 90-95 Fahrenheit so long as the pump and fan are working their ass off.
Hell in a small situation, just go get a motorcycle radiator. Depends on the needs totally.
Watercooling would not be efficient. You would have to engineer over half the parts, and if you did so....
Let me put it this way, there is no way in hell I would waste my time doing this as I could have made more money simply trading!
Dunk em. It's easy.