What is phase cooling?

supposedly its the best type of cooling short of liquid nitrogen.
how much does it cost and is it worth it?

Its basically similar to an a/c system that uses refrigerant for cooling. The good one usually cost up to $1K and can drop cpu temps down to -30c.

No, if u wanted it at 3.0 or 3.2 then yes

man, a 3700 will get 2.9ghz on stock cooling because it runs so damn cool to begin with.
Back to the subject, though. Phase changing will run you about ~$800 and will cool CPU temps to about -10C. Unless you get a really powerful processor, it really isn't worth buying (this wouldn't get your 3700 how much higher than 2.9 at all). It works by have liquids change phase atop the CPU, and when this happens, heat is released. BTW, dry ice is stronger.

its not nearly that expensive -_- a prommie gt2 prolly run you about 600 dollars and keep it well under -20 or -30 C. you can build your own single stage or cascade to go as low as -100 C =D


the basic idea is compressing a gas into a liquid then evaporating it (evap absorbs heat energy)

i'm not an expert in physics... go ask a college physics teacher or a reliable source to explain it to you.

http://xtremesystems.org/forums/forumdisplay.php?f=80

unless that processor has massive potential, no. the highest you would get a 3700 to is about 3.3, and an opteron 146 on air will get to 3.0.

The whole evaporation process makes use of the latent heat of the liquid as it evaporates. For example, if you were to monitor the temperature of boiling water, you would notice the temperature never go above 100C, but the steam itself could go higher in temperature. If you were to plot the observation in temperature on a graph, you would notice a flat plateau where the phase change is occuring, from liquid to steam. For water, i think its something like 2MJ (joules) of energy per litre to turn water to steam. That's a lot of energy. So the same principle is applied to liquids which have much lower boiling points. Not only do you have the energy being absorbed by the heat capacity of the liquid, but also by the latent heat capacity as the liquid evaporates. Thus the energy is removed.