[joemac]

That’s right if you want to cool a CPU to 0 or the freezing point I would recommend at least a 175 W Peltier. The lowest temperature reached using any type of Peltier depends on many factors, one of which is the load being applied. The picture below shows a aquajoe block using a 50 W T.E.C. notice the temperature difference between the hot side and cold side. The block was working using no running water (something you don’t want to do). Do not skimp out on compressing on the Peltier AKA T.E.C. The main reason for this is that when the T.E.C is on it will flex due to the extreme temperatures (again see the picture below) – The hot side will expand and the cold side will contract. Before you choose your power supply pick out the T.E.C. This way you could match your power supply to your T.E.C. Make sure that your power supply can provide the current need to power your T.E.C. If you are going to be looking for a T.E.C to run using a computer supply try to find one that is rated at 16 Volts. The reason for this is that you don’t want to supply the T.E.C with the full 16 V but only with about 75%.