Basically as above...
it's a pretty cool setup to have, you can stack the coolers on top of each other to achieve some serious cooling. but ultimately you have to vent the heat to somewhere, and that'll usually still be inside the case.
you can add peltiers to water cooled setups to increase their cooling capacity. (it increases the heat taken away from the chip, and you'll be venting the heat outside thee case -assuming your radiator is outside the case).
Originally Posted by JogaBonito1502
edit: It would be really cool if they could create a heatsink where the top of the processor sits in a vacuum. That would cool very well
ummm... not really.
in regular air cooling from a heat sink will be by two methods, radiation, and heat is conducted to the air.
if you were to remove all the air from around the heatsink there would be no air to dissipate the heat into. -i.e you'd actually remove the biggest source of heat transference. -and get worse cooling.