Also see the monitoring chipset temperature further down regarding temperature monitoring off peltier's. Personally I think this method is too much off a hazzle for a home user. Super computers also use liquid nitrogen for cooling. I know one private person who does this - but he has very good knowledge about this. Where Asetek delivers the best solution which also outperforms Kryotek in tests.
Alpha make some off the best coolers - and at a reasonable prize.
But if you want more cooling than the Alpha can deliver - I would advise you to skip peltiers and jump right to the Asetek solution. A dual system is under development. And if the space permits - feel free to install a better heatsink with a fan attached. 3dfxcool's microfans is perfect for this purpose. The surface off the heatsink chipset is probably very coarse like this picture - we have lapped in ours so they look like this .