Researchers Use Calculation Errors To Greatly Improve Processor Speed And Power Efficiency

Brad Chacos

A team of researchers from prominent institutions around the world claim that they've figured out how to make computer processors smaller, faster and more power efficient than ever before: by letting chips mess up once in a while. No, seriously. By allowing "inexact" chips to make a pre-calculated amount of errors rather than striving for absolute perfection, the researchers claim that drastic power reductions can be made -- and they already have a working prototype.

The researchers -- from Rice University, Singapore’s Nanyang Technological University, Switzerland’s Center for Electronics and Microtechnology, and the University of California, Berkeley -- use probability to account for the number of errors created by the inexact chip and place limitations on exactly which chip calculations can produce errors, to avoid mistakes during critical processes. Since an inexact chip isn't constantly triple-checking its work for pinpoint accuracy, it also receives a significant processing speed increase compared to traditional processors.

A couple of innovations help inexact chips consume less power than traditional chips. The variance allows the team to "prune" infrequently used sections of the chips to make the hardware smaller, while a technique called "confined voltage scaling" taps into the processing speed increase to reduce power consumption when it isn't needed.

“In the latest tests, we showed that pruning could cut energy demands 3.5 times with chips that deviated from the correct value by an average of 0.25 percent,” study co-author Avinash Lingamneni said in a Rice University press release . “When we factored in size and speed gains, these chips were 7.5 times more efficient than regular chips. Chips that got wrong answers with a larger deviation of about 8 percent were up to 15 times more efficient.”

But what good is a chip that screws up all the time? Plenty of good, as it turns out. While you obviously wouldn't want an inexact chip running, say, critical banking or security systems, the researchers say it could provide significant gains in areas that can have more tolerance for slight errors. Since the human body is hard-wired for basic error correction, the release says that initial markets may include hearing aids and devices that generate pictures.

"We used inexact adders to process images and found that relative errors up to 0.54 percent were almost indiscernible," project co-investigator Christian Enz reports. "Relative errors as high as 7.5 percent still produced discernible images.”

Hey, does that mean Photoshop might get cheaper in the future? In any case, the team hopes to have the first inexact chip-powered prototype hearing aids and educational tablets available sometime in 2013.

Follow Brad on Google+ or Twitter

Around the web

by CPMStar (Sponsored) Free to play