But if you close the top you lose part of the cool factor of the computer.

I studied a bit into this in my high school, while working on oil-cooled transformers, breakers and switches. Without a considerable surface for a static contact(ribbed cage with no airflow), or a well-conductive surface with airflow, the PC will not work. Only breakers and switches work without eithe component, because the oil is not heated constantly, and can cool on it's own. I can't remember the numbers exactly, but I do remember a 400W oil-cooled transformer having a double-circular radiator throughout it's length. And as the PC has none, it leads me to believe it will cook.

If it at first doesn't succeed, build a bigger box.

1) Heat dissipation of anything less than a Prescott is less than 100W

2) The actual heated components of the computer (the CPU and GPU) take up a very small portion of the total system. The GPU has it's heatsink (minus the fan) acting as a passive cooler, and the CPU originally had the heatsink from a Zalman cooler, but was eliminated as it was found to not be needed.

Note that the exposed ciruits - the pins on the CPU particularly - are isolated from the oil, and the oil acts as a heatsink on it's own.

And one thing people here seem to be missing - IT'S BEEN VERIFIED THROUGH EXPERIMENT.

Any time you have a theory, it's just a theory until you actually perform an experiment to confirm or refute the theory. So unless you're prepared to call Tom's Hardware out-and-out liars, and have some experimental evidence yourself to back up your claims, you're pretty much pooched.

Closing the top would just lose you the stench of old rancid oil. ;)

If you use a heat exchanger you wouldn't need to worry about heat transfer through the sides or top so you could stay with the lexan that Tom used (just totally enclosed)... so you'd have a totally visible system.

Then all you'd need is some oil safe neon and you'd have your ride totally pimped.

I was just trying to find out if light machine oil would work. It's clear and cheap (PAG oil would be perfect, but costs large) so you could see everything clearly and wouldn't have to change the oil when it got rancid.