Many of you have shown an interest in getting into extreme overclocking. One of the means and surely the one that requires a lower cost investment is the use of dry ice. For me, this is an excellent alternative to liquid nitrogen and the way to “get your hands dirty” before, why not, launching yourself into LN2. I was lucky enough to be able to do this test with the Bartxstore ECO pot !
The idea of this article/tutorial is to explain what you need to plan ahead, what you will need and how a dry ice session works. It is slightly different from nitrogen. The problem with dry ice is that the price can vary enormously from one distributor to another. Personally, a price of 2.5 €/Kg is what we still find acceptable but sometimes it can be well over 5 euros per kilo.
OK, but what do I need? [nextpage title=”The Bartxstore Eco pot:”]
The Pot:
As I said, you’ll need to invest a good hundred euros to buy a pot. The price of metals at the moment also has an impact on the price of pots. This is the most important element as it is the one that will be filled with dry ice to cool your processor. It is often made of copper or a mix of copper/aluminium. The choice of these materials is due to their very good thermal conductivity. Dry ice pots are a little cheaper than liquid nitrogen pots because the internal maze is relatively simple. Indeed, as you will see in the tests, it is almost impossible to manage the temperature with dry ice, which is a completely different factor to LN2.
An LN2 pot or a specific pot?
For dry ice, it is more interesting to use a specific cup and we will explain why. Take a look below at some pictures of the internal maze of pots. You can see that the internal circuits are more complex than the one of our Eco pot which I will tell you about later.
It is important to remember that liquid nitrogen is liquid (easy) and dry ice comes in the form of ice sticks. The problem with the sticks is that the contact surface with the bottom of the cup is going to be very poor, so you will need to optimise it. Imagine ice cubes in a glass that should cool the base of the glass. The contact with the base will be very bad. By adding water, the water will be cooled by the ice cubes and the contact with the base of the glass will be optimal. We will explain later on how we will optimize this contact for dry ice. But as you will have understood, in a cup with a simple maze, it is easier to optimize the contact with dry ice.
Bart’s Eco Pot:
For this series of tests, we will use an ECO pot made by Bartxstore. Its reference name is CPU LN2/Dice Copper ECO Pot. This pot is sold at a price of 155 euros plus shipping from Poland and is made entirely of copper. Its dimensions are 160 mm high, 60 mm diameter for the base and 54 mm diameter for the top.
It is fixed by 4 threaded rods. It is delivered with all the elements to be compatible with the following sockets: Intel 775/115x/1366/2011/1700 and AMD AM2/AM3/AM4. The good news is that you will also receive Armaflex insulation (6mm sheet, 19mm sheet and a tube for the pot).
The weight of the bucket is about 1 kg. This bucket can also be used for nitrogen, but it will not be as effective as a “real” LN2 pot. The surface area and internal maze is much more limited than a traditional pot for use with liquid nitrogen. Here is a first set of photos of the pot installation and its attachment for the photos.
The idea here is to give you an idea of the installation. For example, all the insulation is missing. You can see where the fixing is to be placed to hold the pot in place. This Eco pot uses a backplate but it is kept away from the back of the socket by spacers. This part must be well insulated.
The base of the pot also has a small hole for the thermal probe. As stated on the brand’s website: “Perfect for begineers who would like to start with extreme overclocking”. If you want to start with extreme overclocking, this Copper ECO Pot is a great choice! [nextpage title=”What you will need: “]
A stable configuration:
This is certainly the most important thing. It’s not when you’re cold that you’ll have to start tweaking and testing things. Ideally, you should already have your best memory profile saved and your OS ready with the various benchmarks you’ll need. Basically, when you go to start testing in the cold, you should only have to worry about the processor, your memory kit or your GPU. Otherwise, you risk wasting precious time and getting frustrated with your first cold session. It is therefore ideal to have already carried out a series of tests in aircooling or water cooling beforehand.
Dry Ice:
This is the most important element because without it, there is no cooling. Let’s start with a short explanation of what dry ice is. Dry ice (-78.5°C) is produced by hydraulically compressing liquid CO2. It was given the name “dry ice” because it leaves no residue after evaporation. This is because the ice sublimates as a gas (not as a liquid) and both the frozen product and its packaging remain intact. Dry ice has a high cooling capacity and has no taste or smell.
Also, be careful with its storage. Do not put it in your freezer. The freezer is not designed for this purpose and you risk damaging it. Dry ice can be stored in its delivery bag and in an isothermal container, but not hermetically sealed! One of the disadvantages is that its shelf life is quite short as you lose a certain quantity every day. It is therefore interesting to get it on the day of your tests or for the next day. If it is cold, leave the container outside.
Acetone or alcohol:
Don’t worry, it’s not for drinking during the tests, though… As dry ice is mostly in stick form, it is necessary to have a liquid to bridge the gap between the base of the bucket and the dry ice sticks. As we have shown on the previous page, without liquid, the contact is very poor. This is why we will choose a simple internal maze, so that the different cavities can be easily filled. Imagine the amount of liquid that has to be poured into the KingPiN T-Rex bucket for example. The best choice is acetone, as it remains in its liquid form down to a temperature of -95.4°C. It can therefore be combined with dry ice, which has a temperature of -78.5°C, without the risk of the acetone turning to ice. 
Acetone is a volatile, very fluid, clear and colourless liquid with a pungent and aromatic odour. Beware of vapours as its volatility is high, about 10 times that of water. The tests should therefore be carried out in a sufficiently ventilated area. Also beware of splashes, which can stain your components if you use too much acetone.
A thermometer :
Even if it is not a requirement as with LN2 tests, it is always a plus. It is possible to find thermometers that accept K-type temperature probes on Amazon. But this is not really a requirement as we will be filling our bucket completely with dry ice. It is almost impossible to play with the temperature with dry ice as with nitrogen.
For our purposes, we will use the KTH K-type thermometer sold by Elmor. It can accommodate two K-type probes. These probes have a wide operating range from -200°C to 1600°C. The KTH K-type thermometer can be powered either by using two AAA batteries or via a USB type C cable. The package includes an acrylic case with a stand to position it face up and a cable for connection to the UART port.
Insulation for your motherboard and pot:
In order to preserve your material, a good insulation is necessary around the socket. You can either use charcoal rubber or neoprene. Charcoal gum takes a little longer to insulate, but is very effective as it is more airtight. As far as the insulation of the pot is concerned, if you opt for the ECO pot model from Bartxstore, it is delivered with insulation for the pot as well as for the back of your motherboard and the socket.
Thermal paste:
This is an essential element to take into account for cold testing. It is best to choose a thermal paste that is designed to “hold up” under cold. Under the action of cold, traditional pastes can “crack”, i.e. they freeze and therefore no longer ensure the transfer role between the base of the pot and the IHS of your processor. This is a bit of a disaster, as you have to reheat your pot to restore the paste to its original texture.
We can recommend KingPin’s KPx High Performance and Thermal Grizzly’s Kryonaut Extreme.
Recommendations to consider:
The use of dry ice, acetone and more generally extreme overclocking requires taking precautions such as being in a well ventilated room. We cannot be held responsible for any consequences that could damage your equipment. By respecting the different steps stated above, you will avoid any problems and will have a good time torturing your equipment 🙂 [nextpage title=”Insulation and bucket installation: “] Now that you know what you need, we can start the installation and preparation of this extreme overclocking session. The first step will be to place either charcoal rubber around the socket or neoprene. Here, I opted for neoprene because the cutouts are quite simple. I used a cutter for the cuts. The idea is to prevent condensation and therefore fine water droplets around the socket.
Don’t forget that you will also need to insulate the back of your motherboard. Here I used charcoal gum to fill in the back of the socket and then a 15mm piece of neoprene. The rear support of the pot is quite particular, hence this choice. I slid the gold spacers through the neoprene.
Then I inserted the 4 threaded rods and tightened them on the other side of the motherboard, not forgetting the plastic washer. Finally, I come back to replace the insulation around the socket.
Putting the thermal paste on the IHS of the processor. We then put the pot with the insulation at the base and tighten the pot on the CPU. As you can see, I used the slot to place the thermal probe. Once in place, all that remains is to slide the insulation from the top.
The test setup:
- Motherboard: MSI MEG Z690 Unify-X(test)
- Processor: Intel i9-12900K Alder Lake (test)
- Memory : 32 GB Teamgroup Delta RGB 6400 MT/s CL40 (test)
- Graphics card: MSI GT 710
- Cooling system: ECO pot + dry ice
- SSD : Western Digital SN850 NVMe SSD M.2
- Power supply : be quiet! Dark Power PRO 12 1500w
- Display: ROG PG27UQ
My personal advice is that if you use too much acetone and/or your pot is not very tall, you risk having splashes and these can leave stains on your components. So remember to protect them with a piece of cardboard for example. That’s it, everything is in place, we can start our series of cold tests. [nextpage title=”Our tests and results under cold conditions: “] As I often say, you don’t start a cold test without having done some tests beforehand. So I have with me my notes from the watercooling tests. It is very important to have this base in order to compare performance numbers. If you decide to upload your scores to Hwbot afterwards, always keep an eye on the tests of other overclockers. It is interesting to compare your results with theirs at the same frequency. To do this, go to the search submission page. For example, I searched for the Cinebench R20 benchmark with an i9-12900K processor to get the results of my future opponents.
Here we go: a little protocol
Personally, before filling the pot, I always go to OS and run a little Cinebench R15. “But are you completely crazy?” No, if your pot is set up properly, it will heat up a bit, but it won’t heat up all the copper. The idea is to heat up the thermal paste so that it sets up properly. During this test, with no load, the CPU went up to 81°C. Another tip is not to change several parameters at the same time such as frequency and/or voltage. The idea is to know in case of a crash what is responsible for it. So we will fill the bottom of the well with acetone and fill it with dry ice. The temperature drops very quickly and our thermometer shows -63.8°C. Be careful, this is not the temperature of the CPU but the temperature of the pot.
Our CPU to start the tests is at 5.0 GHz for a voltage of 1.18 volts. I estimate that the CPU should be between -25 and -30°C. We have no way of reading this temperature. The BIOS and Core Temp simply show us 0°C.
As far as dry ice consumption is concerned, it is mainly during benchmarks that it decreases. The advantage of this type of extreme overclocking is that it’s really stress-free and you can take breaks as you like by just leaving the pot full.
The results with our i9-12900K :
Here’s a table of most of my readings during this 2.5 hour session. If some boxes are empty, it’s because I didn’t run the benchmark. Looking forward to continuing with liquid nitrogen.
Please note that when running Cinebench at 5700MHz in 8P+8E, the CPU temperature turns positive again and rises to 15°C. The best results have been uploaded to Hwbot in order to get personal points as well as for our overclocking.com team. Here are the different screenshots.
It was really fun to prepare this tutorial on how to use dry ice. It’s really fun and if you want to get into extreme overclocking for beginners, I can only advise you to go for it!
The end of the session :
If you have the opportunity to take everything apart and dry it at the end of your overclocking session , do it! Here, the insulation proved sufficient as I had almost no moisture around the socket. Just in one place where the fan was blowing on the memory sticks.
As you can see, there was nothing on the back of the motherboard either, despite a 2.5 hour session. Even if it’s never the most fun part, don’t botch the insulation of your components. [nextpage title=”Conclusion: “] I hope this tutorial on dry ice use has answered most of your questions. If not, feel free to ask them below in comments or directly on our Discord in the #sub-zero section. As you can see, with a simple pot and the right precautions, you can already have fun at temperatures of -55/-65°C. If you’re ready to get into the world of extreme overclocking with dry ice, this ECO pot is a very good choice. Even though the price has increased slightly due to raw material costs, for 155 euros you get everything you need. The mounting is very efficient and you also get the necessary insulation for your pot as well as your motherboard.
As I said, extreme overclocking with dry ice is really interesting because it’s stress free as soon as all precautions are taken. It is an excellent alternative to liquid nitrogen for beginners. The only constraint for me is the price, depending on the delivery person, as well as its conservation. We are not done with dry ice yet, as we will soon be testing the i5-12100F on the Asus ROG Strix B660-F Gaming. Feel free to share your experience and photos on this post in our forum! Finally, you should know that I’m also preparing a video tutorial and certainly a small live session which will be easier to answer your questions!