IBM Applies Evolutionary Approach To Revolutionary Chip

IBM has said that it will deliver an exascale chip within the next five years. The company made the annoucement less than two weeks after the U.S. Department of Energy's Argonne National Laboratory announced the creation of the Exascale Technology and Computing Institute (ETCi). Big Blue has also stated that the chip, based on new technology called CMOS Integrated Silicon Nanophotonics, can be produced on the front end of a standard CMOS manufacturing line and requires no new or special tooling. 

According to ETCi, exascale computing will create supercomputers that are 1,000 times more powerful than the world's current fastest system, China's Tianhe-1A. Exascale computing systems could achieve 1 million trillion floating point operations per second (exaflops). Today's current performance levels are measured in petaflops, a quadrillion operations per second.  

ETCi plans to address a variety of technical challenges over the next 10 years, including developing ultra-low power designs, 3-D chip configurations, massively parallel programming models, silicon photonics, and hybrid multicore architectures. However, it appears that IBM scientists have beaten ETCi to the punch with technology that integrates electrical and optical devices on the same piece of silicon. 

Enabling computer chips to communicate using pulses of light instead of electrical signals, will result in smaller, faster and more power-efficient chips. IBM says the technology enables a variety of silicon nanophotonics components, including modulators, germanium photodetectors and ultra-compact wavelength-division multiplexers. 

A single transceiver channel with all accompanying optical and electrical circuitry occupies only 0.5 mm. IBM wouldn't give a timetable on when the exascale technology will be delivered but did say that exascale computing would be available within the next five years. The next step is establishing manufacturability of this process in a commercial foundry. It wasn't enough to just reach the next level of computing, says IBM; it also had to do so with as little disruption as possible to current CMOS manufacturing technology.

This is a major advance, says analyst Jim Handy of Objective Analysis. "One of the greatest challenges facing today's processor designers is the capacitance of the signal lines. The sheer inertia of trying to push one of these lines from a zero to a one at gigahertz speeds consumes inordinate power, and that power must be supplied by very large transistors that gobble up a lot of the very valuable real estate on a processor chip. IBM, Intel, and others have been looking for a way to replace these signal lines with optical paths for over a decade, and today's announcement is a big step forward in this quest."

While the initial target is exascale computing, IBM says technology tends to ultimately find its way into other lines. It wouldn't comment on the implications for other processors, such as its POWER chip, but did say the new technology is very power efficient. By moving from electrical to optical connections, not only is bandwidth increased, but power consumption is reduced 10 times, an important consideration as the significance of green computing grows.