Passive Submersion Cooling – Oil PC


1. Overview
2. Materials
3. Construction
4. Tests
5. Aftermath



Okay, so when you have a relatively sudden decline of homework and there isn’t any upcoming exams or tests, you get bored. Really bored.

The plan? To submerge the components of a computer in a liquid which acts as an alternative coolant to the fans found in conventional computers. Common sense dictates this as suicidal, as the liquid would be able to conduct electricity, thus short circuiting the components. However, if a pure dielectric liquid is used, no short circuiting would occur as the resistance of the liquid prevents any flow of current within.

Damn; Few weeks later, you find yourself going on a shopping spree for second hand computer components, which total up to a devastating S$600 over. Just to add on, these were decent high performance hardware that is better than 98% of the average people’s computer, and don’t even get me started on the price-versus-performance ratio. If the experimentation doesn’t turn out well, at least we can use it as a nice little gaming or web server. Or so we thought.

Besides, it isn’t very often that you get to set a new milestone in human stupidity.

Difficulty: 1 2 3 4 5 6 7 8 9 10

Cost: 1 2 3 4 5 6 7 8 9 10

Time: 1 2 3 4 5 6 7 8 9 10


CPU AMD Athlon-64 3000+ Venice
Motherboard Abit KN8 nF4
Memory eDevices 512MB X 1 (UCCD)
Video Card ATI X800SE
Power Supply HEC 350 Watts

Lots of Oil

Stock CPU Heatsink w/o Fan

PC Cooler GPU Heatsink w/o Fan


Abit KN8 nF4:

This nForce 4 chipset based motherboard wasn’t exactly what we were looking for, but our budget and desperation forced us to purchase it. There’s onboard audio, LAN, and every basic neccessity except video, which we don’t really care ‘cos we’re getting a graphics card anyway. So far, I’m impressed with this board for its decent overclocking abilities.

Damage done: S$120



Now, that’s a sweet ATI X800SE graphics card you might say. Ah screw it, this puppy doesn’t have Shader Model 3.0 support. But still, it’s decent overall for its price. A quick 3DMark05 run at default clock speeds rates the card at a 3472 score.

Damage done: S$135



There’s nothing much to this, just a cheapo 350W power supply unit that’s starting to fail. It’s making some kind of deep wheezing, sick sound. Maybe it’s just acting pissed off. Damned second hand dealers. I love the UV reactive cables though.



The Assembled PC:
(Runnng on XP-90 w/ Scythe 80mm Fan temporarily)

Our pathetic budget didn’t even allow us to even purchase a chassis, much less a hard disk drive or CD drive. So, we simply dump the computer on the floor and attached our very own hard disk drive and CD drive (which wouldn’t go into the oil duh) to test out.

On air cooling, we managed to overclock the processor, the AMD A64 3000+ to a wonderful 2.8GHz and 246MHz for the RAM.

And in case you’re wondering how fast/slow that is, we ran a quick benchmark:

In Super Pi, a benchmark in which your processor calculates pi up to the one-millionth digit in the shortest possible time, the S$600 oil test dummy scored 33.297 seconds. In comparison, an average 2.8GHz computer would’ve taken almost 50 seconds or so.

We got hold of a plastic container to submerge the PC in the oil…

The Oil PC placed awkwardly in the barely fitting plastic container. No oil yet. This thing produces a hell lot of heat without the cooling fan, so it will be interesting to see how well the oil act as a coolant.

The Oil PC was fun; The Oil PC rocked; The Oil PC owned; For the first few hours. More details in a minute, but first, a very scientific and detailed diagram of the cooling properties of oil.

It started alright. We went to the supermarket nearby, got S$30 worth of cheapass brand cooking oil (lost count of the number of bottles, roughly 8 medium-sized and 2 large). We chose the cooking oil for its refreshing aroma and marvellous colour. Actually, it was helluva cheap and we’re cheap asses. On top of hooking up an unused monitor from a spoilt computer, we threw in the keyboard and mouse that was with the spoilt computer as well. The cables of these components will have to be submerged in the oil as well, Yeah.

We had a hard drive and CD-RW drive that we brought along as well, taken from our own computers.



In came the oil. Bottle after bottle, the coolant level continued to rise. Up past the CPU, up past the RAM. After we depleted our supply of oil, we realised that the graphics card (which was sticking out by quite a fair bit) wasn’t fully submerged. But we decided to ignore that anyway. The computer was switched on while the oil was being poured in, to monitor the temperature. The computer still ran fine. Checking the temperatures, they were considerably lower. Other than the oil being so viscous, this thing was awesome (for the moment).


As the day concluded, the teacher eventually damn well did found out about the experimentation in school. After some exchange of angry words, we had to move to the Physics Lab. I fixed the system up there and let it ran idle overnight. The next day when I returned, the temperature of the CPU was a devastating 60 degrees centigrade! That temperature is still acceptable, but the fact that AMD documented the maximum temperature a Venice core could operate was 65 degrees and I was only running on idle, I decided that it wasn’t safe to leave it operating 24/7 just like that. I definitely need a constant cooling system if I wanted to run 24/7, but our finances are extremely limited. So we were like, “Now what?”.

The mid-year examinations came along, followed by the Mother Tongue O Levels papers. It was almost a miserable month before we saw the Oil PC again. However when we came back, the scent that greeted us was all too familiar. Cooking oil, arghhh. We stared into the oil.

…There were not one, not two, but at least FOUR dead dumb flies who spent their last few moments exploring the Oil PC. Some were floating on the surface, while others were totally submerged at the bottom of the container. It was damn clear even to a primary school kid; The oil was decomposing.

Sorry to spoil your meal, but cooking oil will go rancid, i.e. grow BACTERIA by the gazillions and get someone sick. We’ve just ruined our PC permanently, and even if we try to get the cooking oil out of our printed circuits, (they are porous weaves of fiberglass and epoxy) they too will rot. We’ll see soon enough – we’ll have to throw out your experiment just because of the stink, never mind our health in the longer term.

(No pictures of the aftermath at all due to the fact that… y’all know, I’m more interested to clean up the mess than documenting it.)

Right. So we immediately poured the oil down the sink, with half of the intention was to choke it with the high viscousity of the oil. We tried our best to clean up the physics lab, but evidently our performance rivals that of the most poorly paid janitors on their worst day. We kept all the oily computer components in an oily plastic bag on an oily table. We stared blankly at the retardedness of the situation, of how that S$600 could’ve saved hundreds of childrens in third-world countries instead.

Alright, so now we have oily computer components in anvoily plastic containervsurrounded by a wonderful aroma of decomposing oil, which has left its horrendously delightfulvimprint despite it being gotten rid of. Untilvwe can figure outvourvnext intelligent move, the Oil PC will be redundantly idling in the Physics Lab.



I brought home the Oil PC, attempted to wash it all and managed to salvage the CPU and RAM. At least, we saved $200 from the $600! -.-


Disclaimer: All experiments and projects presented here are highly dangerous and purely intended for educational and experimental purposes only. Do not attempt them at any rate.