Recent technology trends in computer systems include movement toward higher compute module power and higher rack power with 3D chip stacks out at the leading edge.  These trends result in systems that cannot be cooled with conventional air cooling.   Single phase water cooling has been the technology of choice in addressing these trends, but it has risks associated with potential leaks, biological contamination, and freeze damage. It also does not scale down to the very small channels required to cool 3D stacks of large high power chips.   An alternative approach is to utilize two-phase flow boiling of a dielectric fluid, which has both benefits and challenges. 

This talk will present challenges, approaches and results for two phase flow boiling in a near term innovative cold plate implementation as well as in a farther future 3D chip stack embedded cooling configuration.  The results demonstrate capability to effectively cool conventional 2D/2.5D systems at a much lower, more sustainable cooling power cost relative to air cooling and the capability to build and effectively cool high power 3D chip stacks while mitigating the risks associated with single phase water.