Going with that setup, the temperature drop would have to accumulate, and the rad would keep the temps around air temp when they enter the chiller res. If you have a large enough tec, its do-able, but you'd see better results by putting the tec directly on the CPU. A better idea would be to try some form of phase change to chill your equipment, tecs are powerhungry and have low cooling capabilities when compared to a phase system. However, even if you just drop the rad, that setup should work, provided that the tec is of a high enough wattage. I suggest checking out the xtremesystems forums and looking at the chilled liquid systems.