I recall something about liquid (something, could be nitrogen, or perhaps even mercury) that was chilled; PC Boards were then submersed in the liquid to keep cool.
Maybe on Crays?
dunno about Crays..... but definitely on Control Datas ETA 10s designed to replace the CYBER 205 in 1988-1990 at the von Nueman supercomputer center in princeton we had 2 eta 10s.... each with large CPU boards that were immersed in tanks of liquid nitrogen. If we had a AC problem the operator were trained to do the quickest possible shut down on the machines..... even so with in five minutes the temp inside the machine room went up by 10 degrees -- **************************************************************** The COOK Report on Internet, 431 Greenway Ave, Ewing, NJ 08618 USA (609) 882-2572 (phone & fax) cook@cookreport.com Index to 9 years of the COOK Report at http://cookreport.com From now through Sept 15th half price sale on university library site license and access to ALL back issues. Site license $575 and all back issues $300. http://cookreport.com/sale.shtml ****************************************************************