Sounds like a good idea. Id like to try the vacuum idea with the check valve but pulling a vacuum may warp the motherboard and also it would be beyond the abilities of most home users. My aim was to develop a process that could be easily duplicated at home with the minimal of supplies and effort.

I doubt a vacuum would damage the motherboard, but the high pressure differental will certianly cause any weakness in the seals to give way.

With the dessicant, is there much to worry about?

Another option is to replace the air inside the cube with something without any water in it. Nitrogen and argon are good coices, as they are harmless and since they are heavier than air, you can "pour" them in to insure you get all the air out. Gas supplies can be easily gotten at local welding supply shops.

For some motherboards.. what about puting studs in that can pass through the four mounting holes and then be screwed down to make a good, firm seal against a rubber gasket? No glues needed.

This thing still running?

Jason, I have an idea I'd like to see tried, yet I have no idea when I'd have time to try it. It may be a much less expensive and easier implemented alternative.

Here's what I suggest: Using a old board and chip to make sure it's going to work before trying this on something you can't afford to lose. Why not stick a copper block on the cpu and silicone around it, then hook the peltier to it, then hook on your water block, etc. Paint the underside of the board with liquid electrical tape, then slowly pour melted candle gel over the board until it's level with the center of the first copper block. I don't think you'd want it too close to the hot side of the pelt.

It should seal the board from condensation permanently. If you wanted to spruce it up with LED's, EL-wire, or something, just use a screwdriver or other stick-like thing to push it into the gel while it's cooling.

I'd make a mold around the cpu to set the gel just there. Only drawback I can see is that you'd want the board to stay horizontal.

What do you think, is it worth a try?

I agree that would probably work but the idea was to come up with something less drastic. Most users wouoldnt go as far as melting wax or painting their motherboard. BTW is there any electro static problems with spray paint cans? Your idea is sound, and many more radical enthusiasts have done very similar stuff, including me. But most typical users interested in sub ambient cooling wouldnt go that far.

I've read on a couple of sites where spray paint cans of water repellent were used with success.