Nvidia’s Bill Dally has posted about the company’s progress towards exascale computing, boosted by a $12.4 million grant from the U.S. Department of Energy. He mentions that it would be possible to build an exascale supercomputer today, if you could supply enough power:

Exascale systems will perform a quintillion floating point calculations per second (that’s a billion billion), making them 1,000 times faster than a one petaflop supercomputer. The world’s fastest computer today is about 16 petaflops.

One of the great challenges in developing such systems is in making them energy efficient. Theoretically, an exascale system could be built with x86 processors today, but it would require as much as 2 gigawatts of power — the entire output of the Hoover Dam. The GPUs in an exascale system built with NVIDIA Kepler K20 processors would consume about 150 megawatts. The DOE’s goal is to facilitate the development of exascale systems that consume less than 20 megawatts by the end of the decade.

If the industry succeeds in driving down supercomputer power consumption to one fortieth of what it is today, I guess it also follows that tablets like the one on which I am typing now will benefit from much greater power efficiency. This stuff matters, and not just in the HPC (High Performance Computing) market.