Oh yes, CO2 and Freon whould work better than water, but you would need to add in a compressor to get them to work. The compressor will be noisy, difficult to install and will suck up alot of juice. It will aso be expensive. You're talking sub-ambient cooling here so you would also have to guard against atmospheric water condensation.
It'll cost you in excess of $500 to set up a CO2/Compressed Air/Freon cooling system (I looked into it once, about 2 years ago). Water cooling can be had for less than $200, plus is virtually silent. Air cooling (HSF) can be had for as little as $20.
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