Roto# I dont disagree but comparing a CRAY, or IBM Mainframe which were also cooled with chilled Flourinert is 100% different than our rigs.
The machines above use an endless supply of chilled service water ( normally chilled as part of the HVAC system for the building its in). From there the transfer from the chilled water to the Flourinert happens over another heat exchanger. Then from there multiple pumps (with redundancy) move the coolant at high pressures and velocity through the machine. One pump for an IBM mainframe costs around 15,000$. Some of the old Crays also used LN2 to chill Flourinert and cool the system.. .the components for that cooling system is in the millions of dollars.
See Air cooling has none of those expensive requirements and risk that the LC setup has used. Today can provide CLOSE to the cooling that many of the consumer watercooling systems can.
Using watercooling on any production machine ( using consumer products) is insane I think (any machine which you rely on and depend on). that is EXACTLY the main reason I dont run watercooling in my main PC at home (while I do have it in a couple other machines)... I needed one machine that I will not need to worry about die'n due to a small leak or pump failure, or anything. Besides with todays HSF's I wouldnt gain THAT much performance ( just maybe slightly quieter.)
Its all about MTBF as bri said. The only way a cooling system becomes feasable in the top end super computers is when its built with parts and engineering that cost millions to develop. or they just use HSF's and some fans which give the same MTBF but just a lil louder
The fast athlon Linux cluster is nifty and all, but I see the watercooling aspect as being quite a big investment for a small payout over what you would see with a modified air cooled setup. Also for the cost of a big rig like that... Prolly could have bought faster CPU's
