Hi Phil
I found my old 12V water pump from water steriliser (long forgotten adventure with cichlides) and it will be circulating the cooling water. Currently CPU is water cooled, and the graphic card and motherboard chipset will be as well soon. I'm waiting for Peltier modules to come and I'm going to drop coolant temperature as low as possible without condensation. uC is going to control Peltiers by PWM in 8 bit mode. PWM duty cycle will be dependent upon comparing set temperature with readout.
For example coolant temp = set temp then duty cycle = 0 ( peltier off). Temp difference x2 = PWM register (up to 255) so coolant temp variation going to be around 1.28 centigrade creating from 0% to 100% peltier duty cycle.
Looks like this small silencing project going to be a monster one .
At last that's the theory, maybe somebody have some suggestions ???
Graphic card and manifold parts :
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