I started to play around with some compressor cooling devices, otherwise known as fridges, freezers or airconditioners ;) As with everything it started with a lot of reading, some doing, more reading, well you get the point... Anyways, I am now running an old and portable split airconditioner on hydrocarbons instead of the already escaped R22 refrigerant. With all this experimenting I got reminded that my computer does not really like to do hard gaming work on these hot days. There are already a lot of infos out there on how to use water and/or heatpipes to cool your system. One thing that they all have in common is that you need a chiller to cool the water. Now, there are really tons of options here - from using an old bar fridge to hold the water up to big direct chillers that can be used 24/7 and cost a small fortune. Here in Victoria the weather might be more forgiving but up north the humidity will be your main enemy if you want to use any decent cooling system. Imagine 90% humitiy and the water condensing on pipes and coolers inside your computer... Some systems compensate here by using a temp of around 12°C at the lowest to minimise the risk of condensation. But I think we can do better for cheaper if we are willing to get dirty and salvage some scrap. If it also a great way to protect your computer in a dusty and hot workshop enviroment! Let me explain the thought: Considering the costs for a decent air cooled system over the expense for just a basic water cooling kit it might be worth spending the extra money otherwise. What makes a normal and not overclocked computer go too hot assuming it is clean and free from dust? Right - the outside temperature and how hard we actually use it. Normal systems are designed to work at a room temp between 18 and 24°C, we are often lucky to have it under 30 in the summer. Getting a CPU to just under 70° if the outside air is already over 30° is hard if not impossible. But what if the computer would be in one of these fancy server rooms that are kept at 16° throughout the year? Problem solved, just win the lottery to get your server room build. Step back a bit and think again ;) If we make an additional and well insulated enclosure to put the computer in we would only need to worry about making it pretty much air tight and keeping the inside always under 20°C. Now follow me to my imaginary shopping trip... First step is getting a decent sized cooler box - you can build your own of course I would go for these oversizes Esky chests. Next step is a visit to the local hard rubbish collection or scrap yard. We look for a bar fridge or water cooling tower that has a condenser that will fit on the side or back of our cooling box. Prefer something old running on R22 instead of R134a if you can. If the system already has one or two service ports for filling even better, otherwise see you get one from a different fridge or freezer. The fun starts back home where we now make a big mess. The cooling system needs to come apart and if not a tower the fridge around it has to go without damaging pipes or condensers. Perfect would be to have a working system and to keep it in this condition to avoid the illegal escape or refrigerant. It also make it easier than having to refill it again. On the other hand getting a system that is already professionally evacuated as most scrap yards now do anyway can make the modding easier - up to your skill set and options to have the system checked and filled. Once we have a naked cooling system we get the cold side into the cooler box. Either by creating a slot to slide it in or by feeding the hoses through holes if you plan to do your own thing in terms of testing and filling. The compressor part and "hot side" are mounted securely to the outside of the box. If you still have the thermostat working and connected you can now check your homebuild fridge. To get the computer inside you have several option, IMHO the easiest is use one big enough hole to get all cables to the outside. You want this hole to end up as airtight as possible, I found candle wax to be a good sealer if you place some painters tape on the box first. So far this was the easy part, the hard part is now to make sure the humidity inside the box stays as low as possible. When the compressor starts cooling the evaporator will go to very low temperatures, even if you set the thermostat to 10° the cold side will condese or even freeze the moisture in the air. Unlike with direct cooling option inside your computer we now have a "cold trap" outside the coputer that we use to our advantage! Easiest option here is to have a catchment under the cold side to collect the condensing water and to let it discharge through a small tube to the outside. Once the system was operating for a few days there should be no moisture left inside our box unless it is not properly sealed. At this point you could be tempted to just set the thermostat to the coldest possible - I advise against it! Imagine the inside of the box is below freezing - the capacitors won't like it to start with and since we now have all surface subcooled the moisture can condense everywhere not warm enough, including your mainboard. A temp of around 10°C should be more than enough for normal gaming and gives the compressor a chance to turn off every now and then so any ice can drop off and exit. If you like the idea use it and make a featured Instructable out of it, my time is too limited at the moment to get serious with this.