Swiftech MCW6500-T TEC (Peltier) Assisted Water Blockhardnrg - June 14, 2007
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Okay, case modding and mains wiring done and dusted, so what's next? Now you have to prepare the motherboard to protect it against condensation. When a surface is colder than the surrounding air (below dewpoint), the moisture in the air condenses on the surface. A common example of this, is when a can or glass of ice cold beverage quickly becomes covered in tiny droplets of water. As you know, water and electronics are seldom a good combination. You need to get some conformal coating, which is basically a spray on electrically insulating layer to prevent electrical short circuits from surface moisture. I used Electrolube DCA SCC3 Conformal Coating. Make sure you read the instructions, you will almost certainly be told not to shake the can before spraying, contrary to the instinctive action. This stops air bubbles in the protective layer being applied to the motherboard.
Spray the back of the motherboard, concentrating on the area directly under the socket, in the near vicinity and then vertically down, so that if droplets form and roll down the motherboard, they won't cause a short-circuit. I had to use a filtered paint mask to spray this stuff as it is quite harmful to inhale.
You need to let the conformal coating dry before you continue. The stuff I used says it needs to be thermally cured in a drying station or something like that. I guess that's a unit that is heated and extracts the fumes away. In my case this consisted of my bathroom with the extractor fan turned on, and a minute or so with the hairdryer set to low heat. The stuff is highly flammable so don't go crazy trying to thermally cure the coating super fast. Just warm it gently to get it going and then leave it to cure. When it's done, you can attach the neoprene pad to the area directly under the centre of the socket.
Pretty easy right? Next you are going to do the business side of the motherboard, masking off all the important sockets, header pins, edge connectors, jumpers, etc. I didn't mask off the chipset fan, so it got some coating on it. It probably would be a good idea to remove the chipset fan altogether and mask off the chipset itself. I used multiple layers of masking and parcel tape on the CPU socket to ensure it was sealed from the conformal coating.
So, same deal with the no-shake, spray, gentle heat, and cure. As I run "naked" processors with no heatspreader, I thought it would be a good idea to mask off the CPU die and conformal coat the surrounding CPU PCB.
This is where the cold plate area is going to be so it seemed to make sense in this situation.
Now, the neoprene gasket that you get seemed to be fairly small, with a very narrow, flimsy "wall" along the top edge. I decided to make a surrounding neoprene gasket to provide some sealing around the gap underneath the 939 retention bracket.
So above you see the supplied gasket, the extra gasket I made, and the two together. Below you see the supplied gasket fitted to the motherboard and then the extra gasket around it.
The supplied gasket has a peel-back adhesive layer on the bottom. I used Bison Kit Contact Adhesive to glue my extra neoprene gasket to the motherboard.
When I was happy with that seal, I moved onto adding the Luberex dielectric grease.
This stuff seals electrical contacts from moisture, but still allows electrical current to pass through it. You put a generous helping in the socket itself and then place the CPU down in the socket and let the grease squeeze out the sides.
With the CPU in place you can now add the Arctic Silver Ceramique thermal compound. This is used instead of Arctic Silver 5, because Ceramique works better at sub-zero temperatures and the TEC-block is capable of producing temperatures below freezing.
Then add even more grease around the CPU to seal all the air spaces.
At this point I have to pause for a moment. After I completed the subsequent steps of installation and fired up the computer, it didn't POST. It didn't even beep to tell me something was wrong. Only the four diagnostic LEDs on my DFI NF4 Ultra-D told me that the CPU wasn't being recognised. After some testing with a Thermalright SLK-948u heatsink, I reached the conclusion that somehow traces of conformal coating had seeped into the socket, maybe from underneath or around the edges. This was preventing the CPU pins making contact inside the socket.
Nightmare situation? Sort of. I had to buy some industrial solvent cleaner to clean and dissolve the conformal coating inside the socket. I couldn't get hold of the recommended Electrolube DRG SCC3 Conformal Coating Remover Gel, so I picked up some Servisol Coldklene 110 from work instead. It was even more toxic than the conformal coating! But it worked and after leaving it to soak in the socket overnight, finally my CPU was recognised by the motherboard.
So, that sucked, haha. Anyway, with the CPU socket functional again, I was all set to finishing up the installation.